How is ED Diagnosed?

Finding the cause of your ED will help your health care provider find the best treatment choices for you. Most health care providers will ask you about your general health and the history of your erection problem. Your health care provider may also give you a physical exam and order lab tests.

Health and ED History

Your doctor will ask you questions about your health and lifestyle. For example, certain medicines may be helping to cause your ED. Also, smoking or alcohol use can affect erections. Being open with your health providers will allow them to find the best treatment choices for you. It's important to discuss different things that you can do to improve your condition and your health.

What Questions Might My Health Care Provider Ask?

Questions About Health Problems

Some questions you may be asked are:

What health problems do you have?
What medicines do you take?
Do you smoke, drink, or use other drugs? If so, how much?
Do you have any prior history of surgery or radiation therapy, especially in the pelvic area?
Do you have urinary problems?

Questions About ED

Asking questions about your history of ED can help your health care provider find out whether your problems are with desire for sex, erection, ejaculation, or orgasm (climax). Some of these questions will be personal and may seem embarrassing. Honest answers will help find the cause and best treatment for your ED.

Some questions about your ED that you may be asked are:

How long have you had these symptoms? Did they start slowly or all at once?
Do you wake up in the morning with an erection? Do you wake up during the night with an erection?
If you do have erections, how firm are they? Is penetration difficult?
Do your erections change at different times such as when entering a partner, during stimulation by mouth or with masturbation?
Do you have problems with sex drive, arousal, ejaculation, or orgasm (climax)?
How is this problem affecting your enjoyment of sex?
What effect is this problem having on your relationship (if you are in one)?

Questions About Stress and Emotional Health

Your health care provider may ask you questions about feelings such as depression or worry. He or she may also ask about problems in your relationship with a partner. Some health care providers may ask if it is okay to talk to your sex partner, also.

Some questions you may be asked about your emotional health are:


How is your relationship with your partner? Has anything changed lately?
How satisfied are you with your sex life? Has anything changed lately?
Are you under a lot of stress most of the time? Or has anything especially upsetting happened to you?
Do you have any mental illnesses or depression? Are you taking any meds for depression or anxiety?

Physical Exam

A physical exam checks overall health. This may involve checking your blood pressure, penis and testicles. You may need to have a rectal exam to check your prostate. These tests are not painful and may give useful information about the cause of your ED. Most patients do not need a lot of testing before starting treatment.

Lab Tests

To test for diseases that cause ED, your health care provider may order blood tests and collect a urine sample.

Other Tests

Erectile Function Tests

Your health care provider will test to see how the blood vessels, nerves, muscles and other tissues of your penis and pelvic area are working. Normal nocturnal penile tumescence (NPT), or healthy automatic erections during sleep, shows that your nerves and blood supply are working properly.

Imaging

A duplex ultrasound shows what's happening inside your body by bouncing sound waves off an organ to form pictures on a monitor. It checks for blood flow, vein leaks, scars on erectile tissue and some signs of clogged arteries. If you take this test, you may be given an injection into your penis to cause an erection. The technician can then see how the blood flow and pressure changes in your penis, as well as how it expands. These images are compared to images of the limp penis.

What Causes ED?

ED can result from health or emotional problems or from both. Lower blood flow or harm to nerves in the penis can lead to erection problems. Physical Causes of ED

Some things that can increase the chances of getting ED (known as risk factors) are:

Age over 50
High blood sugar (diabetes)
High blood pressure
High cholesterol
Smoking
Cardiovascular disease
Drug or alcohol abuse
Obesity
Lack of exercise
Even though ED becomes more common as men age, growing old is not the cause of the problem. ED can be an early sign of a more serious health problem. Finding and treating the cause(s) of your ED can improve your overall health and well-being.

ED may happen because:

Not enough blood flows into the penis
Many health issues can reduce blood flow into the penis, such as heart disease, high blood sugar (diabetes), and smoking.
The penis cannot store blood during an erection
A man with this problem cannot keep an erection because blood does not stay trapped in the penis. This condition can occur in men of any age.
Nerve signals from the brain or spinal cord do not reach the penis
Certain diseases, injury or surgery in the pelvic area can harm nerves in the penis.

Emotional Causes of ED

Sex activity needs the mind and body to work together. Emotional or relationship problems can cause or worsen ED.

Some emotional issues that can cause ED are:

Depression
Relationship conflicts
Stress at home or work
Worry about sexual performance

What are the Symptoms of ED?

When you have ED, it is hard to get or keep an erection that is firm enough for sex. Most men have trouble with erections from time to time, but in some men it is a regular and more bothersome problem. ED can cause:

Low self-esteem
Performance anxiety
Depression
Stress

ED may affect the quality of a marriage or intimate relationships.

5 natural herbs that will make your erection stronger and last longer!

If you have ever thought of using Viagra (Sildenafil) to help strengthen your erection or make it last longer, then think again. Known to increase the blood supply to the blood vessels of your penis, the little blue pill has a number of side effects like headaches and painful erections. What’s more this drug should not be used if you have heart disease.

But if you’d still like to use something to give your erection a boost, here are some herbs that work just as well.

Ginseng

A herb used in Chinese medicine, ginseng contains a compound called ginsenoside that acts on the body the same way as Vigra, sans the side effects. In fact, according to a study[1] conducted in 2002, men who had ginseng for eight weeks showed better results than those who merely took a placebo. Even though, the herb doesn’t show immediate results like Viagra, using it for a period of time has been known to improve sexual performance. You may also like to read: Is Viagra bad for young people? (Sex doubt of the day).

Epimedium (Horny goat weed)

Found only in China, epimedium has around 50 species – and extracts from some of them are believed to have aphrodisiacal properties. Icaarin, a flavonoid present in these plants is believed to boost sexual performance and is present in many herbal supplements. Like Viagra, Icaarin also works by inhibiting an enzyme called PDE5 in the penis. You may also like to read about yoga asanas to beat erectile dysfunction.

Saw palmetto

Saw palmetto is a wonder herb used for treating many ailments, especially prostate enlargement and urinary tract infections. Even though, it’s efficacy as an impotence drug has not been established it is considered good for sexual health as an enlarged prostate or any urological ailment can seriously hamper a person’s desire and performance.

Yohimbe

Derived from the bark of pausilinia yohimbe, this herb has proven to be useful in treating erectile dysfunction. The herb works as a sexual stimulant by blocking alpha-2 andrenergic receptors and improving blood flow to the penis. Additionally, it helps in the production of the chemical norepinephrone which in turn helps in getting an erection.

A drug called yohimbine hydrochloride has been approved by the US FDA for treating erectile dysfunction.

Ginkgo bilboa

Growing only in some parts of China, ginkgo bilboa works as an aphrodisiac by improving blood circulation in your body. Most erectile dysfunction issues are caused due to lack of blood supply to the penis, and increasing blood circulation in the body should be the number one agenda for people suffering from the ailment.

Sometimes, manufacturers just add some herbs to regular Viagra and sell it as herbal Viagra. Be wary of such products.

Natural Treatment of Erectile Dysfunction

June is Men's Health Month, and a good time to examine the common male condition known as erectile dysfunction, or ED. According to the American Urological Association, more than 25 million men in the U.S. suffer from some sort of ED, but because the level of distress is so variable with this condition, only 5 percent of them have sought treatment.

Symptoms and Causes

Commonly called male impotence, ED is the inability to achieve or maintain penile erections sufficient for intercourse. ED often has a psychological component, and counseling with a psychotherapist or sex therapist often resolves the problem. ED can also be a symptom of cardiovascular disease and diabetes, both of which can impair blood supply to the penis. In addition, many medications, including those prescribed for high blood pressure and mental health conditions, can interfere with sexual functioning. Tobacco, cocaine, stimulants and alcohol may also play a role.

Suggested Lifestyle Changes

Bear in mind that some of the problems leading to erectile dysfunction may lend themselves to the following non-drug (and cost-free) solutions:

Stop smoking. Nicotine can reduce genital blood flow and impair potency.
Check your meds. ED and sexual dysfunction are unfortunate side effects of many drugs. Consult with your pharmacist or doctor regarding substituting alternate medication without these effects.
Limit alcohol consumption. Alcohol’s depressive effects can have a negative impact on sexual functioning.
Shape up. ED is often linked with restricted blood flow to the penis. Keep your heart and arteries in good condition by maintaining a healthy weight, and following a diet high in fruits, vegetables and whole grains. Avoid saturated fats and trans fats. Regular aerobic exercise can both improve blood flow to the genitals and reduce the stress that can contribute to ED.
Deal with anxiety, depression and stress. These feelings may undermine desire and potency. Practice a daily stress-reduction technique such as breath work, meditation or yoga. Talk with your partner openly and honestly about your needs – and their needs – to help ease relationship tensions and avoid resentment and misunderstandings.
Don’t worry about your age. Sexual activity needn’t end because of age – that’s a myth you can discard.

Supplements

Ginkgo. This herb may improve arousal in both men and women, perhaps by increasing blood flow to the genitals. It should not be used by those on blood thinners such as coumadin. Yohimbe. This comes from the bark of an African tree, Pausinystalia yohimbe, is the basis of several pharmaceutical drugs used to treat impotence. It contains an alkaloid, yohimbine, which previously was the only drug listed in the Physician's Desk Reference as a sexual booster. This herb, however prized as an aphrodisiac, can have some side effects (agitation, anxiety and insomnia) that make many men prefer not to use it. Yohimbe bark and extracts are occasionally available in health food stores, but I do not recommend them.

As an alternative, try taking ashwagandha or a standardized extract of Asian ginseng. Ashwagandha, from the roots of a plant in the nightshade family called Withania somnifera, is reputed to be a mild aphrodisiac and has long been popular in India. Asian ginseng, or Panax ginseng, is a good general stimulant and sexual energizer. For either, follow the dosage on the package, and give it a six or eight week trial to have an effect. Both ashwagandha and Asian ginseng are generally safe (but Asian ginseng can raise blood pressure and cause irritability and insomnia in some people).

Natural Remedies for Erectile Dysfunction

For centuries, men have tried all sorts of natural remedies for erectile dysfunction (ED) -- the repeated inability to get or maintain an erection firm enough for sexual intercourse. But do they really work? It is simply not scientifically known at this point. Furthermore, you take these remedies at your own risk, because their safety profiles have not been established. What follows are commentaries by experts and reviews in the field of alternative treatments that are available over the counter for erectile dysfunction.

"Just because there is evidence doesn't mean it's good evidence," says Andrew McCullough, MD, associate professor of clinical urology at New York University Langone Medical Center in New York City, and one of the original clinical investigators for the ED drug Viagra (sildenafil). "And before men with ED start down the naturopathic route, it's smart to make sure that there isn't some underlying medical condition that needs to be corrected." Moreover, it is estimated that 30 million American men have erectile dysfunction, and 70% of cases are a result of a potentially deadly condition like atherosclerosis, kidney disease, vascular disease, neurological disease, or diabetes. Additionally, ED can also be caused by certain medications, surgical injury, and psychological problems.

Experts feel that treating erectile dysfunction on your own, without consulting a doctor, is unsafe. "If you have ED, the first thing you need is a diagnosis," says impotence expert Steven Lamm, MD, a New York City internist and the author of The Hardness Factor (Harper Collins) and other books on male sexual health. He says men with severe erectile dysfunction probably need one of the prescription ED drugs, which include Levitra (vardenafil) and Cialis (tadalafil) as well as Viagra. But, he says, mild ED -- including the feeling that "you're not as hard as you could be" -- often responds to natural remedies.

Acupuncture. Though acupuncture has been used to treat male sexual problems for centuries, the scientific evidence to support its use for erectile dysfunction is equivocal at best. In 2009, South Korean scientists conducted a systematic review of studies on acupuncture for ED. They found major design flaws in all of the studies, concluding that "the evidence is insufficient to suggest that acupuncture is an effective intervention for treating ED."

Arginine. The amino acid L-arginine, which occurs naturally in food, boosts the body's production of nitric oxide, a compound that facilitates erections by dilating blood vessels in the penis. Studies examining L-arginine's effectiveness against impotence have yielded mixed results. A 1999 trial published in the online journal BJU International found that high doses of L-arginine can help improve sexual function, but only in men with abnormal nitric oxide metabolism, such as that associated with cardiovascular disease. In another study, published in 2003 in the Journal of Sex & Marital Therapy, Bulgarian scientists reported that ED sufferers who took L-arginine along with the pine extract pycnogenol saw major improvements in sexual function with no side effects. Arginine can be helpful, says Geo Espinosa, ND, director of the Integrative Urological Center at NYU Langone Medical Center. Espinosa says that men with known cardiovascular problems should take it only with a doctor's supervision; L-arginine can interact with some medications.

DHEA. Testosterone is essential for a healthy libido and normal sexual function, and erectile dysfunction sufferers known to have low testosterone improve when placed on prescription testosterone replacement therapy. Similarly, studies have shown that taking over-the-counter supplements containing DHEA, a hormone that the body converts to testosterone and estrogen, can help alleviate some cases of ED. But DHEA can cause problems, including suppression of pituitary function, and its long-term safety is unknown, says McCullough. For this reason, many experts discourage use of the supplements.

Ginseng. Korean red ginseng has long been used to stimulate male sexual function, but few studies have tried systematically to confirm its benefits. In one 2002 study involving 45 men with significant ED, the herb helped alleviate symptoms of erectile dysfunction and brought "enhanced penile tip rigidity." Experts aren't sure how ginseng might work, though it's thought to promote nitric oxide synthesis. "I would recommend ginseng [for men with ED]," says Espinosa. Discuss with your doctor before taking it since ginseng can interact with drugs you may already be taking and cause allergic reactions.

Pomegranate juice. Drinking antioxidant-rich pomegranate juice has been shown to have numerous health benefits, including a reduced risk for heart disease and high blood pressure. Does pomegranate juice also protect against ED? No proof exists, but results of a study published in 2007 were promising. The authors of this small-scale pilot study called for additional research, saying that larger-scale studies might prove pomegranate juice's effectiveness against erectile dysfunction. "I tell my patients to drink it," says Espinosa. "It could help ED, and even if it doesn't, it has other health benefits."

Yohimbe. Before Viagra and the other prescription erectile dysfunction drugs became available, doctors sometimes prescribed a derivative of the herb yohimbe (yohimbine hydrochloride) to their patients suffering from ED. But experts say the medication is not particularly effective, and it can cause jitteriness and other problems. "It's not a great drug," says McCullough. "And I suspect the herb is not as potent as the pharmaceutical version." What's more, evidence shows that yohimbe is associated with high blood pressure, anxiety, headache, and other health problems. Experts discourage its use.

Horny goat weed. Horny goat weed and related herbs have purportedly been treatments for sexual dysfunction for years. Italian researchers found that the main compound in horny goat weed, called icariin, acted in a similar way as drugs like Viagra.

Ginkgo biloba. Known primarily as a treatment for cognitive decline, ginkgo has also been used to treat erectile dysfunction -- especially cases caused by the use of certain antidepressant medications. But the evidence isn't very convincing. One 1998 study published in the Journal of Sex & Marital Therapy found that it did work. But a more rigorous study, published in Human Pharmacology in 2002, failed to replicate this finding. "Ginkgo has come out of fashion in the past few years," says Ronald Tamler, MD, assistant professor of medicine and codirector of the men's health program at Mount Sinai Medical Center in New York City. "That's because it doesn't do much. I can say that in my practice, I have not seen ginkgo work -- ever."

No matter what erectile dysfunction treatment or treatments a man ultimately decides upon, experts say it's important to eat healthily and to avoid smoking and heavy drinking. Moreover, adequate exercise, stress reduction, and sleep can improve erectile dysfunction in many. In addition, says Lamm, "A loving, receptive, and responsive partner is a home run. After all, this is still a couple's issue."

ED, Impotence

Erectile dysfunction (impotence) facts

Erectile dysfunction (ED), also known as impotence, is the inability to achieve or sustain an erection for satisfactory sexual activity.
Symptoms of erectile dysfunction include the inability to have or to sustain a penile erection to complete satisfactory sexual activity.
Erectile dysfunction is common; experts have estimated that erectile dysfunction affects 30 million men in the United States.
The causes of erectile dysfunction include aging, high blood pressure, diabetes mellitus, cigarette smoking, atherosclerosis, depression, nerve or spinal cord damage, medication side effects, alcoholism or other substance abuse, and low testosterone levels.
Erectile dysfunction is treatable in all age groups.
Treatments include psychotherapy, adopting a healthy lifestyle, oral PDE5 inhibitors (Viagra, Levitra, Cialis, Stendra, and Staxyn), intraurethral medications (MUSE), intracavernosal injections, vacuum devices, surgery, and working with doctors to avoid medications that can impair erectile function.
Before using over-the-counter and/or supplements, a discussion with a doctor is strongly recommended.
New research is ongoing in the field of erectile dysfunction to find more improved and effective therapies.
What is erectile dysfunction (ED)?
Erectile dysfunction (ED), also known as impotence, is the inability to achieve or sustain an erection for satisfactory sexual activity. Erectile dysfunction is different from other conditions that interfere with male sexual intercourse, such as lack of sexual desire (decreased libido) and problems with ejaculation and orgasm (ejaculatory dysfunction). This article focuses on the evaluation and treatment of erectile dysfunction.

What are erectile dysfunction symptoms and signs?

Symptoms of erectile dysfunction may include the following:

Penile erection occurs but it is not maintained for the length of sexual activity
Penile erection that is not firm enough to penetrate the vagina
Inability to obtain a penile erection

What is normal penis anatomy?
The penis contains two chambers, called the corpora cavernosa, which run the length of the upper side of the penis (see figure 1 below). The urethra, which is the channel for urine and ejaculate, runs along the underside of the corpora cavernosa. Filling the corpora cavernosa is a spongy tissue consisting of smooth muscles, fibrous tissues, veins, and arteries. A membrane, called the tunica albuginea, surrounds the corpora cavernosa. Veins located in the tunica albuginea drain blood out of the penis. The corpus spongiosum helps maintain the urethra open during an erection for passage of the ejaculate (sperm and prostatic fluid).

How common is erectile dysfunction?
Erectile dysfunction (ED, impotence) varies in severity; some men have a total inability to achieve an erection, others have an inconsistent ability to achieve an erection, and still others can sustain only brief erections. The variations in severity of erectile dysfunction make estimating its frequency difficult. Many men also are reluctant to discuss erectile dysfunction with their doctors due to embarrassment, and thus the condition is underdiagnosed. Nevertheless, experts have estimated that erectile dysfunction affects 18-30 million men in the United States.

While erectile dysfunction can occur at any age, it is uncommon among young men and more common in the elderly. By age 45, most men have experienced erectile dysfunction at least some of the time. According to the Massachusetts Male Aging Study, complete impotence increases from 5% among men 40 years of age to 15% among men 70 years and older. Population studies conducted in the Netherlands found that some degree of erectile dysfunction occurred in 20% of men between ages 50-54 and in 50% of men between ages 70-78. In 1999, the National Ambulatory Medical Care Survey counted 1,520,000 doctor-office visits for erectile dysfunction. Other studies have noted that approximately 35% of men 40-70 years of age suffer from moderate to severe ED, and an additional 15% may have milder forms. Further studies report similar findings.

How does erection occur?
Erection begins with sexual stimulation. Sexual stimulation can be tactile (for example, by a partner touching the penis or by masturbation) or mental (for example, by having sexual fantasies, viewing porn). Sexual stimulation or sexual arousal generates electrical impulses along the nerves going to the penis and causes the nerves to release nitric oxide, which in turn increases the production of cyclic GMP (cGMP) in the smooth muscle cells of the corpora cavernosa. The cGMP causes the smooth muscles of the corpora cavernosa to relax and allow rapid blood flow into the penis. The incoming blood fills the corpora cavernosa, making the penis expand.

How is erection sustained?
The pressure from the expanding penis compresses the veins (blood vessels that drain the blood out of the penis) in the tunica albuginea, helping to trap the blood in the corpora cavernosa, thereby sustaining erection. Erection is reversed when cGMP levels in the corpora cavernosa fall, causing the smooth muscles of the corpora cavernosa to contract, stopping the inflow of blood and opening veins that drain blood away from the penis. The levels of the cGMP in the corpora cavernosa fall because it is destroyed by an enzyme called phosphodiesterase type 5 (PDE5).

What are erectile dysfunction risk factors?
The common risk factors for ED include the following:

Advanced age
Cardiovascular disease
Diabetes mellitus
High cholesterol
Cigarette smoking
Recreational drug use
Depression or other psychiatric diseases

What causes erectile dysfunction?
The ability to achieve and sustain erections requires the following:

A healthy nervous system that conducts nerve impulses in the brain, spinal column, and penis
Healthy arteries in and near the corpora cavernosa
Healthy smooth muscles and fibrous tissues within the corpora cavernosa
Adequate levels of nitric oxide in the penis

Erectile dysfunction can occur if one or more of these requirements are not met. The following are causes of erectile dysfunction, and many men have more than one potential cause:

Aging: There are two reasons why older men are more likely to experience erectile dysfunction than younger men. First, older men are more likely to develop diseases (such as heart attacks, angina, cardiovascular disease, strokes, diabetes mellitus, and high blood pressure) that are associated with erectile dysfunction. Second, the aging process alone can cause erectile dysfunction in some men, primarily by decreasing the compliance of the tissues in the corpora cavernosa, although it has been suggested, but not proven, that there is also decreased production of nitric oxide in the nerves that supply the corporal smooth muscle within the penis. Diabetes mellitus: Erectile dysfunction tends to develop 10-15 years earlier in diabetic men than among nondiabetic men. In a population study of men with type I diabetes for more than 10 years, erectile dysfunction was reported by 55% of men 50-60 years of age. The increased risk of erectile dysfunction among men with diabetes mellitus may be due to the earlier onset and greater severity of atherosclerosis that narrows the arteries and thereby reduces the delivery of blood to the penis. When insufficient blood is delivered to the penis, it is not possible to achieve an erection. Diabetes mellitus also causes erectile dysfunction by damaging both sensory and autonomic nerves, a condition called diabetic neuropathy. Smoking cigarettes, obesity, poor control of blood glucose levels, and having diabetes mellitus for a long time further increase the risk of erectile dysfunction in people with diabetes. In addition to atherosclerosis and/or neuropathy causing ED in diabetes, many men with diabetes also develop a myopathy (muscle disease) as their cause of ED in which the compliance of the muscles in the corpora cavernosa is decreased, and clinically this presents as an inability to maintain the erection.
Hypertension (high blood pressure): People with essential hypertension or arteriosclerosis have an increased risk of developing erectile dysfunction. Essential hypertension is the most common form of hypertension; it is called essential hypertension because it is not caused by another disease (for example, by kidney disease). It is not clearly known how essential hypertension causes erectile dysfunction; however, those with essential hypertension have been found to have low production of nitric oxide by the arteries of the body, including the arteries in the penis. High blood pressure also accelerates the progression of atherosclerosis, which in turn can contribute to erectile dysfunction. Scientists now suspect that the decreased levels of nitric oxide in patients with essential hypertension may contribute to erectile dysfunction.
Cardiovascular diseases: The most common cause of cardiovascular diseases in the United States is atherosclerosis, the narrowing and hardening of arteries that reduces blood flow. Atherosclerosis typically affects arteries throughout the body and is aggravated by hypertension, high blood cholesterol levels, cigarette smoking, and diabetes mellitus. When coronary arteries (arteries that supply blood to the heart muscle) are narrowed by atherosclerosis, heart attacks and angina occur. When cerebral arteries (arteries that supply blood to the brain) are narrowed by atherosclerosis, strokes occur. Similarly, when arteries to the penis and the pelvic organs are narrowed by atherosclerosis, insufficient blood is delivered to the penis to achieve an erection. There is a close correlation between the severity of atherosclerosis in the coronary arteries and erectile dysfunction. For example, men with more severe coronary artery atherosclerosis also tend to have more erectile dysfunction than men with mild or no coronary artery atherosclerosis. Some doctors suggest that men with new onset erectile dysfunction should be evaluated for silent coronary artery diseases (advanced coronary artery atherosclerosis that has not yet caused angina or heart attacks).
Cigarette smoking: Cigarette smoking aggravates atherosclerosis and thereby increases the risk for erectile dysfunction.
Nerve or spinal cord damage: Damage to the spinal cord and nerves in the pelvis can cause erectile dysfunction. Nerve damage can be due to disease, trauma, or surgical procedures. Examples include injury to the spinal cord from automobile accidents, injury to the pelvic nerves from prostate surgery for cancer (prostatectomy), radiation to the prostate, surgery for benign prostatic enlargement, multiple sclerosis (a neurological disease with the potential to cause widespread damage to nerves), and long-term diabetes mellitus. Substance abuse: Marijuana, heroin, cocaine, methamphetamines, crystal meth, and alcohol abuse contribute to erectile dysfunction. Alcoholism, in addition to causing nerve damage, can lead to atrophy (shrinking) of the testicles and lower testosterone levels. Low testosterone levels: Testosterone (the primary sex hormone in men) is not only necessary for sex drive (libido) but also is necessary to maintain nitric oxide levels in the penis. Therefore, men with hypogonadism (diminished function of the testes resulting in low testosterone production) can have low sex drive and erectile dysfunction.
Medications: Many common medicines produce erectile dysfunction as a side effect. Medicines that can cause erectile dysfunction include many used to treat high blood pressure, antihistamines, antidepressants, tranquilizers, and appetite suppressants. Examples of common medicines that can cause erectile dysfunction include propranolol (Inderal) or other beta-blockers, hydrochlorothiazide, digoxin (Lanoxin), amitriptyline (Elavil), famotidine (Pepcid), cimetidine (Tagamet), metoclopramide (Reglan), indomethacin (Indocin), lithium (Eskalith, Lithobid), verapamil (Calan, Verelan, Isoptin), phenytoin (Dilantin), gemfibrozil (Lopid), amphetamine/dextroamphetamine (Adderall), and phentermine.
Depression and anxiety: Psychological factors may be responsible for erectile dysfunction. These factors include stress, anxiety, guilt, depression, widower syndrome, low self-esteem, posttraumatic stress disorder, and fear of sexual failure (performance anxiety). It is also worth noting that many medications used for treatment of depression and other psychiatric disorders may cause erectile dysfunction or ejaculatory problems.

How is erectile dysfunction diagnosed?
Patient history

A diagnosis of erectile dysfunction is made in men who have repeated inability to achieve and/or maintain an erection for satisfactory sexual performance for at least three months. Candid communication between the patient and the doctor is important in establishing the diagnosis of erectile dysfunction, assessing its severity, and determining the cause. During patient interviews, doctors try to answer the following questions:

Is the patient suffering from erectile dysfunction or from loss of libido or a disorder of ejaculation (for example, premature ejaculation)?
Is erectile dysfunction due to psychological or physical factors? Healthy men have involuntary erections in the early morning and during REM sleep (a stage in the sleep cycle with rapid eye movements). Men with psychogenic erectile dysfunction (erectile dysfunction due to psychological factors such as stress and anxiety rather than physical factors) usually maintain these involuntary erections. Men with physical causes of erectile dysfunction (for example, atherosclerosis, smoking, and diabetes) usually do not have these involuntary erections.
Are there physical causes of erectile dysfunction? A prior history of cigarette smoking, heart attacks, strokes, and poor circulation in the extremities suggest atherosclerosis as the cause of the erectile dysfunction. Diminished sensation of the penis and the testicles, bladder dysfunction, and decreased sweating in the lower extremities may suggest diabetic nerve damage. Loss of sexual desire and drive, lack of sexual fantasies, gynecomastia (enlargement of breasts), and diminished facial hair suggest low testosterone levels. Is the patient taking medications that can contribute to erectile dysfunction (see causes above)?

Physical examination
The physical examination can reveal clues for physical causes of erectile dysfunction. For example, if the penis does not respond as expected to touching, a problem in the nervous system may be the cause. Small testicles, lack of facial hair, and enlarged breasts (gynecomastia) can point to hormonal problems such as hypogonadism with low testosterone levels. A reduced flow of blood as a result of atherosclerosis can sometimes be diagnosed by finding diminished arterial pulses in the legs or listening with a stethoscope for bruits (the sound of blood flowing through narrowed arteries). Unusual characteristics of the penis itself could suggest the root of the erectile dysfunction, for example, bending of the penis with painful erection could be the result of Peyronie's disease. Particular attention is paid to any underlying risk factors for erectile dysfunction.

Laboratory tests
The following are common laboratory tests to evaluate erectile dysfunction:

Complete blood counts
Urinalysis: An abnormal urinalysis may be a sign of diabetes mellitus and kidney damage.
Lipid profile: High levels of LDL cholesterol (bad cholesterol) in the blood promotes atherosclerosis.
Blood glucose levels: Abnormally high blood glucose levels may be a sign of diabetes mellitus.
Blood hemoglobin A 1c: Abnormally high levels of blood hemoglobin A 1c in patients with diabetes mellitus establish that there is poor control of blood glucose levels.
Serum creatinine: An abnormal serum creatinine may be the result of kidney damage due to diabetes.
Liver enzymes and liver function tests: Advanced liver disease (cirrhosis) can result in hormonal imbalance and gonad dysfunction leading to low testosterone levels. Thus, evaluation for liver disease may be necessary in cases of erectile dysfunction.
Total testosterone levels: Blood samples for total testosterone levels should be obtained in the early morning (before 8 a.m.) because of wide fluctuations in the testosterone levels throughout the day. A low total testosterone level suggests hypogonadism. Measurement of bio-available testosterone may be a better measurement than total testosterone, especially in obese men and men with liver disease, but measurement of bio-available testosterone is not widely available.
Other hormone levels: Measurement of other hormones beside testosterone (luteinizing hormone [LH], prolactin level, and cortisol level) may provide clues to other underlying causes of testosterone deficiency and erectile problems, such as pituitary disease or adrenal gland abnormalities. Thyroid levels may be routinely checked as both hypothyroidism and hyperthyroidism can contribute to erectile dysfunction.
PSA levels: PSA (prostate specific antigen) blood levels and prostate examination to exclude prostate cancer is important before starting testosterone treatment since testosterone can aggravate prostate cancer.
Other blood tests: Evaluation for hemochromatosis, lupus, scleroderma, zinc deficiency, sickle cell anemia, cancers (leukemia, colon cancer) are some of the other potential tests that may be performed based on each individual's history and symptoms.

Imaging tests
In a setting of a previous pelvic trauma, X-rays may be performed to assess various bony abnormalities. Ultrasound of the penis and testicles is done occasionally to check for testicular size and structural abnormalities. Ultrasound with Doppler imaging can provide additional information about blood flow of the penis. Rarely, an angiogram may be performed in cases in which possible vascular surgery could be beneficial.

Other tests
Prostaglandin E1 injection test is sometimes performed to determine the penile blood flow. Prostaglandin is directly injected into the corpora cavernosa in order to cause dilation of blood vessels and promote blood flow into the penis. If erection ensues, it confirms normal or adequate blood flow to the penis. This can also provide information about possible therapeutic options.

Monitoring erections that occur during sleep (nocturnal penile tumescence) can help distinguish between erectile dysfunction of psychological and physical causes. A band is worn around the penis for two to three successive nights and it can signal intensity and duration of erections if they occur. If nocturnal erections do not occur, then the cause of erectile dysfunction is likely to be physical rather than psychological, however, tests of nocturnal erections are not completely reliable. Scientists have not standardized the tests and have not determined in whom they should be done.

Direct vibrational stimulation (biothesiometry) is occasionally done to evaluate penile nerve function. Small electromagnetic electrodes are placed on the shaft of the penis and vibration amplitude is slightly adjusted until sensation is noted by the patient. Although this test does not measure the exact nerve function, it serves as a screening method to detect any sensory nerve deficit as the cause of ED. Psychosocial examination

A psychosocial examination using an interview and questionnaire may reveal psychological factors contributing to erectile dysfunction. The sexual partner also may be interviewed to determine expectations and perceptions encountered during sexual intercourse.

What drugs treat erectile dysfunction?
Medications for erectile dysfunction include the following:

Testosterone
Oral phosphodiesterase type 5 (PDE5) inhibitors (sildenafil [Viagra], vardenafil [Levitra], tadalafil [Cialis]), avanafil [Stendra])
Intracavernosal injections (papaverine, phentolomine, and PGE1 [Trimix], alprostadil injection [Caverject, Edex])
Intraurethral suppositories (MUSE)
L-arginine

A doctor can help decide what medication(s) may be the best for the patient.

What is the treatment for erectile dysfunction? The following are treatments for erectile dysfunction:

Working with doctors to select medications that do not impair erectile function
Making lifestyle improvements (for example, quitting smoking and exercising more)
Taking drugs to treat ED such as sildenafil (Viagra), vardenafil (Levitra), tadalafil (Cialis), or avanafil (Stendra)
Inserting medications into the urethra (intraurethral suppositories: MUSE)
Injecting medications into the corpora cavernosae (intracavernosal injections)
Vacuum constrictive devices for the penis
Penile prostheses
Psychotherapy
Adjusting medications that may cause or contribute to erectile dysfunction

Many common medications for treating hypertension, depression, and high blood lipids can contribute to erectile dysfunction (see above). Treatment of hypertension is an example. There are many different types (classes) of antihypertensive medications (medications that lower blood pressure); these include beta-blockers, calcium channel blockers, diuretics (medications that increase urine volume), angiotensin converting enzyme inhibitors (ACE inhibitors), and angiotensin receptor blockers (ARBs). Antihypertensives may be used alone or in combination to control blood pressure. Different classes of antihypertensives have different effects on erectile function. Inderal (a beta-blocker) and hydrochlorothiazide (a diuretic) are known to cause erectile dysfunction, while calcium channel blockers and ACE inhibitors do not seem to affect erectile function. On the other hand, angiotensin receptor blockers (ARBs) such as losartan (Cozaar) and valsartan (Diovan) may actually increase sexual appetite, improve sexual performance, and decrease erectile dysfunction. Therefore, choosing an optimal antihypertensive combination is an important part of treating erectile dysfunction. Lifestyle improvements

Quitting smoking, exercising regularly, losing excess weight, curtailing excessive alcohol consumption, controlling hypertension, and optimizing blood glucose levels in patients with diabetes are not only important for maintaining good health but also may improve or even prevent erectile function. Some studies suggest that men who have made lifestyle improvements experience increased rates of success with oral medications.

Oral phosphodiesterase type 5 (PDE5) inhibitors
The common PDE5 inhibitor drugs approved in the United States are sildenafil (Viagra), vardenafil (Levitra), tadalafil (Cialis), or avanafil (Stendra). Actual head-to-head trials between these drugs have not been done to date to see which is the superior drug. Details on each of these medications for erectile dysfunction are outlined below.

Sildenafil (Viagra)
What is sildenafil (Viagra)?
Sildenafil (Viagra) was the first oral phosphodiesterase type 5 (PDE5) inhibitor approved by the FDA in the United States for the treatment of erectile dysfunction (it is not approved for women). Sildenafil inhibits PDE5, which is an enzyme that destroys cGMP. By inhibiting the destruction of cGMP by PDE5, sildenafil allows cGMP to accumulate. The cGMP in turn prolongs relaxation of the smooth muscle of the corpora cavernosa. Relaxation of the corpora cavernosa smooth muscle allows blood to flow into the penis resulting in increased engorgement of the penis. In short, sildenafil increases blood flow into the penis and decreases blood flow out of the penis.

How effective is sildenafil (Viagra)?
Sildenafil is used for the treatment of erectile dysfunction of either physical or psychological cause. It has been found to be effective in treating erectile dysfunction in men with coronary artery disease, diabetes mellitus, hypertension, depression, coronary artery bypass surgery, and men who are taking antidepressants and several classes of antihypertensives.

In randomized controlled trials, an estimated 60% of men with diabetes, and 80% of men without diabetes experienced improved erections with sildenafil.

How should sildenafil (Viagra) be administered?
Sildenafil is available as oral tablets at doses of 25 mg, 50 mg, and 100 mg. It should be taken approximately one hour before sexual activity. In some men, the onset of action of the drug may be as early as 11-20 minutes. Sildenafil should be taken on an empty stomach for best results since absorption and effectiveness of sildenafil can be diminished if it is taken shortly after a meal, particularly a meal that is high in fat.

What is the dose of sildenafil (Viagra)?
In prescribing sildenafil, a doctor considers the age, general health status, and other medication(s) the patient is taking. The usual starting dose for most men is 50 mg, however, the doctor may increase or decrease the dose depending on side effects and effectiveness. The maximum recommended dose is 100 mg every 24 hours, however, many men will need 100 mg of sildenafil for optimal effectiveness, and some doctors are recommending 100 mg as the starting dose.

Metabolism (breakdown) of sildenafil is slowed by aging, liver and kidney dysfunction, and concurrent use of certain medications (such as erythromycin [an antibiotic] and protease inhibitors for HIV). Slowed breakdown allows sildenafil to accumulate in the body and potentially may increase the risk of side effects. Therefore in men over 65, in men with substantial kidney and liver disease, and in men who also are taking protease inhibitors, the doctor will initiate sildenafil at a lower dose (25 mg) to avoid accumulation of sildenafil in the body. A protease inhibitor ritonavir (Norvir) is especially potent in increasing the accumulation of sildenafil, thus men who are taking Norvir should not take sildenafil doses higher than 25 mg and at a frequency of no greater than once in 48 hours.

What are the side effects of sildenafil (Viagra)?
Sildenafil has been found to be well tolerated without important side effects. The reported side effects are usually mild and include headache, flushing, nasal congestion, nausea, dyspepsia (stomach discomfort), diarrhea, and abnormal vision (seeing a bluish hue or brightness).

Sildenafil can cause hypotension (abnormally low blood pressure that can lead to fainting and even shock) when given to patients who are taking nitrates (for heart disease). Therefore, patients taking nitrates daily should not take sildenafil. Nitrates are used most commonly to relieve angina (chest pain due to insufficient blood supply to the heart muscle because of narrowing of the coronary arteries); these include nitroglycerine tablets, patches, ointments, sprays, and pastes, as well as isosorbide dinitrate, and isosorbide mononitrate. Other nitrates such as amyl nitrate and butyl nitrate also are found in some recreational drugs called "poppers."

Sildenafil should be used cautiously in men on alpha-blockers such as doxazosin (Cardura), terazosin (Hytrin), and tamsulosin (Flomax). There have been occasional reports of low blood pressure in men who have taken the two classes of drugs simultaneously and therefore it is recommended that there be at least a span of four to six hours between the ingestion of sildenafil and alpha-blockers.

There have been rare reports of priapism (prolonged and painful erections lasting more than six hours) with the use of PDE5 inhibitors such as sildenafil, vardenafil, and tadalafil, especially when sildenafil is used in combination with injection of medications into the corpora cavernosa or intraurethral suppositories. Patients with blood cell diseases such as sickle cell anemia, leukemia, and multiple myeloma have higher than normal risks of developing priapism. Untreated priapism can cause injury to the penis and lead to permanent impotence. Therefore, sildenafil should not be used in combination with intraurethral suppositories and corpora cavernosa injections. If there is prolonged erection (longer than four hours), immediate medical assistance should be obtained.

Is it safe for men with heart disease to use sildenafil (Viagra)? Sildenafil has been found to be effective and safe in the treatment of erectile dysfunction in men with stable heart disease due to atherosclerosis of the coronary arteries, provided that they are not on any type of nitrates. The real concern is not as much the safety of sildenafil but the risk of sexual activity in triggering heart attacks or abnormal heart rhythms in patients with heart disease.

The risk of developing heart attacks or abnormal heart rhythms during sex is low in men with well-controlled hypertension, mild disease of the heart valves, well-controlled heart failure, mild and stable angina (with a favorable treadmill stress test), successful coronary stenting or bypass surgery, and a remote history of heart attack (more than eight weeks previously). Sildenafil can be used safely in men in these lower-risk groups.

The risk of heart attack or abnormal heart rhythms during sex is higher in men with unstable angina (angina that occurs at rest or with minimal exertion), poorly controlled hypertension, moderate to severe heart failure, moderate to severe disease of the heart valves, recent heart attack (less than two weeks previously), potentially life-threatening disorders of heart rhythm such as recurrent ventricular tachycardia, and moderate to severe disease of the heart muscles. In these men, doctors usually stabilize or treat the heart conditions before prescribing sildenafil.

Before starting sildenafil for erectile dysfunction, a doctor may need to determine whether the heart can safely achieve the workload necessary for sexual activity. For example, in men with coronary artery heart disease, a doctor may perform a treadmill stress test to determine whether there is adequate blood supply to the heart muscle while exercising at levels comparable to sexual activity.

Vardenafil (Levitra)
What is vardenafil (Levitra)?
Vardenafil (Levitra) was the second oral medicine approved by the U.S. FDA for the treatment of erectile dysfunction. Like sildenafil (Viagra), vardenafil (Levitra) inhibits PDE5 which destroys cGMP (as discussed earlier).

How effective is vardenafil (Levitra)?
Vardenafil was evaluated in four multicenter, randomized, placebo-controlled trials involving more than 2,400 men (78% white, 7% black, 2% Asian, 3% Hispanic) with erectile dysfunction. Two of these trials were conducted in special erectile dysfunction populations; one in men with diabetes mellitus, another in men who developed erectile dysfunction after prostate surgery. The doses of vardenafil in the four studies were 5 mg, 10 mg, and 20 mg.

In all four studies, vardenafil was significantly better than placebo in improving men's ability to achieve and maintain erections in all age categories (less than 45, 45-65, and greater than 65 years of age) and in all races.

How should vardenafil (Levitra) be administered?
The recommended starting dose of vardenafil is 10 mg taken orally approximately one hour before sexual activity. The dose may be adjusted higher or lower depending on efficacy and side effects. The maximum recommended dose is 20 mg, and the maximum recommended dosing frequency is no more than once per day. Vardenafil can be taken with or without food.

What are the side effects of vardenafil (Levitra)?
Vardenafil is generally well tolerated with only mild side effects. These side effects include headache, flushing, nasal congestion, dyspepsia, body aches, dizziness, nausea, and increased blood levels of the muscle enzyme creatine kinase.

There have been rare reports of priapism (prolonged and painful erections lasting more than six hours) with the use of oral PDE5 inhibitors such as vardenafil, sildenafil, and tadalafil. Men with blood cell diseases such as sickle cell anemia, leukemia, and multiple myeloma have higher than normal risks of developing priapism. Untreated priapism can cause injury to the penis tissue and lead to permanent loss of potency. If there is prolonged erection (longer than four hours), immediate medical assistance should be sought.

Who should not use vardenafil (Levitra)?
Vardenafil (Levitra) can cause hypotension (abnormally low blood pressure, which can lead to fainting and even shock) when given to patients who are taking nitrates. People taking nitrates daily should not take vardenafil. Most commonly used nitrates are medications to relieve angina (chest pain due to insufficient blood supply to heart muscle because of narrowing of the coronary arteries). These include nitroglycerine tablets, patches, ointments, sprays, pastes, and isosorbide dinitrate and isosorbide mononitrate. Other nitrates such as amyl nitrate and butyl nitrate are found in some recreational drugs called poppers.

Vardenafil should not be used with alpha-blockers, medicines used to treat high blood pressure and benign prostate hypertrophy (BPH), because the combination of vardenafil and an alpha-blocker may lower the blood pressure greatly and lead to dizziness and fainting. Examples of alpha-blockers include tamsulosin (Flomax), terazosin (Hytrin), doxazosin (Cardura), alfuzosin (Uroxatral), and prazosin (Minipress).

Men with a rare heart condition known as long QT syndrome should not take vardenafil since this may lead to abnormal heart rhythms. The QT interval is the time it takes for the heart's muscle to recover after it has contracted. The QT interval is measured with an electrocardiogram (EKG). Some people have longer than normal QT intervals, and they may develop potentially life-threatening abnormal heart rhythms, especially when given certain medications. Since long QT syndrome can be inherited, men with a family history of long QT syndrome should not take vardenafil. Furthermore, vardenafil is not recommended for men who are taking medications that can affect the QT interval such as quinidine (Quinaglute, Quinidex), procainamide (Pronestyl, Procan-SR, Procanbid), amiodarone (Cordarone), and sotalol (Betapace).

There is insufficient information on the safety of vardenafil in men with the following conditions:

Unstable angina (chest pain due to coronary artery disease that occurs at rest or with minimal physical exertion)
Low blood pressure (a resting systolic blood pressure less than 90 mm Hg)
Uncontrolled high blood pressure (greater than 170/110 mm Hg)
Recent stroke or heart attack (within six months)
Uncontrolled, potentially life-threatening abnormal heart rhythms
Severe liver disease
Severe kidney failure requiring dialysis
Severe heart failure or disease of the heart's valves, for example, aortic stenosis
Retinitis pigmentosa
Therefore, men with these conditions should not use vardenafil without having these conditions evaluated and stabilized first. For example, men with uncontrolled high blood pressure should have their blood pressure controlled; and men with potentially life-threatening abnormal heart rhythms should have these rhythms controlled.

When there is angina or heart failure, the doctor may need to determine whether the heart has enough reserve to safely carry out the work necessary for sexual activity by performing cardiac treadmill stress testing.

What precautions should be taken when using vardenafil (Levitra)?
Metabolism (breakdown) of vardenafil can be slowed by aging, liver disease, and concurrent use of certain medications (such as erythromycin, ketoconazole [Nizoral], and protease inhibitors). Slowed breakdown allows vardenafil to accumulate in the body and potentially increase the risk for side effects. Therefore, in men over 65 years of age, with liver dysfunction, or who are also taking medication(s) that can slow the breakdown of vardenafil, the doctor will initiate vardenafil at low doses to avoid its accumulation. For example

men taking erythromycin or ketoconazole should not take more than 5 mg of vardenafil in a 24-hour period;
men taking high doses of ketoconazole (Nizoral) should not take more than 2.5 mg of vardenafil in a 24-hour period;
men with moderately severe liver disease also should not take more than a 5 mg dose of vardenafil in a 24-hour period;
men taking the protease inhibitor (for the treatment of HIV/AIDS) indinavir (Crixivan) should not take more than 2.5 mg of vardenafil in a 24-hour period;
men taking another protease inhibitor ritonavir (Norvir) should not take more than 2.5 mg of vardenafil every 72 hours.

Tadalafil (Cialis)
What is tadalafil (Cialis)?
Tadalafil (Cialis) is the third oral medicine approved by the U.S. FDA for the treatment of erectile dysfunction. Like sildenafil (Viagra) and vardenafil (Levitra), tadalafil inhibits PDE5 (as described earlier).

How effective is tadalafil (Cialis)?
The safety and efficacy of tadalafil in the treatment of erectile dysfunction was evaluated in 22 clinical trials involving more than 4,000 men. Seven of these trials were randomized, prospective, placebo-controlled studies of 12 weeks' duration. Two of these studies (involving 402 men) were conducted in the United States, and the other five studies (involving 1,112 men) were conducted outside the United States. Two of these trials were conducted in special populations with erectile dysfunction; one in men with diabetes mellitus, another in men who developed erectile dysfunction after nerve-sparing prostate cancer surgery.

Effectiveness of tadalafil in these studies was assessed using a sexual function questionnaire. Study participants also were asked if they were able to achieve vaginal penetration and to maintain erections long enough for successful intercourse.

In all seven trials, tadalafil was significantly better than placebo in improving men's ability to achieve and maintain erections. Improvements in erectile function was observed in some patients at 30 minutes after taking a dose; and improvements can last for up to 36 hours after taking Cialis when compared to placebo.

How should tadalafil (Cialis) be administered?
The recommended starting dose of tadalafil for most patients is 10 mg taken orally approximately one hour before sexual activity. The dose may be adjusted higher to 20 mg or lower to 5 mg depending on efficacy and tolerability. The maximum recommended dosing frequency is once per day, although for many patients tadalafil can be taken less frequently since the improvement in erectile function may last 36 hours. Tadalafil may be taken with or without food. Tadalafil is also available in 2.5 mg or 5 mg dosages for daily use.

What are the side effects of tadalafil (Cialis)?
Tadalafil is generally well tolerated with only mild side effects. The most common side effects reported include headache, indigestion, back pain, muscle aches, facial flushing, and nasal congestion.

Back pain and muscle aches occurred in less than 7% of patients and usually occurred 12-24 hours after taking tadalafil. The back pain and muscle aches associated with tadalafil were characterized by mild to moderate muscle discomfort in the lower back, buttocks, and thighs, often aggravated by lying down. The back and muscle aches resolved in most patients without treatment within 48 hours. When treatment was necessary, acetaminophen (Tylenol) and nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin, Advil) or naproxen (Aleve) were effective. Approximately 0.5% of all the patients using tadalafil discontinued the drug due to back pain or muscle aches.

Reports of abnormal vision were rare; it occurred in less than 0.1% of patients using tadalafil.

There have been rare reports of priapism (prolonged and painful erections lasting more than six hours) with the use of oral PDE5 inhibitors such as vardenafil, sildenafil, and tadalafil. Men with blood cell diseases such as sickle cell anemia, leukemia, and multiple myeloma have higher than normal risks of developing priapism. Untreated priapism can cause injury to the penile tissue and lead to permanent loss of potency. If there is prolonged erection (longer than four hours), immediate medical assistance should be sought. Who should not use tadalafil (Cialis)?

Tadalafil can cause hypotension (abnormally low blood pressure, which can lead to fainting and even shock) when given to patients who are taking nitrates. Patients taking nitrates daily should not take tadalafil. Most commonly used nitrates are medications to relieve angina (chest pain due to insufficient blood supply to heart muscle because of narrowing of the coronary arteries). These include nitroglycerine tablets, patches, ointments, sprays, pastes, and isosorbide dinitrate and isosorbide mononitrate. Other nitrates such as amyl nitrate and butyl nitrate are found in some recreational drugs called poppers.

Tadalafil should not be used with alpha-blockers (except Flomax), medicines used to treat high blood pressure and benign prostate hypertrophy (BPH) because the combination of tadalafil and an alpha-blocker may lower the blood pressure greatly and lead to dizziness and fainting. Examples of alpha-blockers include tamsulosin (Flomax), terazosin (Hytrin), doxazosin (Cardura), alfuzosin (Uroxatral), and prazosin (Minipress). The only alpha-blocker that can be used safely with tadalafil is tamsulosin (Flomax). When tadalafil (20 mg) was given to healthy men taking 0.4 mg of Flomax daily, there was no significant decrease in blood pressure and so patients on this dose of tamsulosin (Flomax) can be prescribed tadalafil. The only alpha-blocker that has not been tested with tadalafil is alfuzosin (Uroxatral) and no recommendations can be made regarding the interaction between the two.

Tadalafil is not recommended for men with the following conditions:

Unstable angina (chest pain due to coronary artery disease that occurs at rest or with minimal physical exertion)
Low blood pressure (a resting systolic blood pressure less than 90 mm Hg)
Uncontrolled high blood pressure (greater than 170/110 mm Hg)
Recent stroke or heart attack (within six months)
Uncontrolled, potentially life-threatening abnormal heart rhythms
Severe liver disease
Severe heart failure or disease of the heart valves (for example, aortic stenosis)
Retinitis pigmentosa
Therefore, men with these conditions should not use tadalafil without having these conditions evaluated and stabilized first. For example, men with uncontrolled high blood pressure should have their blood pressure controlled; and men with potentially life-threatening abnormal heart rhythms should have these rhythms controlled.

When there is angina or heart failure, the doctor may need to determine whether the heart has enough reserve to safely carry out the work necessary for sexual activity by performing cardiac treadmill stress testing.

What precautions should be taken when using tadalafil? In most healthy men, some of the drug will remain in the body for more than two days after a single dose of tadalafil. Metabolism (clearing of the drug from the body) of tadalafil can be slowed by liver disease, kidney disease, and concurrent use of certain medications (such as erythromycin, ketoconazole, and protease inhibitors). Slowed breakdown allows tadalafil to stay in the body longer and potentially increase the risk for side effects. Therefore, the dose and frequency of tadalafil has to be lowered in the following examples:

Medications such as erythromycin, ketoconazole (Nizoral), itraconazole (Sporanox), ritonavir (Norvir), and indinavir (Crixivan) can slow the breakdown of tadalafil. Therefore men taking these medications should not take more than 10 mg of tadalafil and should not take tadalafil more frequently than every 72 hours.
No tadalafil dose adjustment is necessary for men with only mild kidney disease. Men with moderately severe kidney impairment should start tadalafil at 5 mg every 24 hours and not to exceed the maximum dose of 10 mg taken every 48 hours. In men with severe kidney disease and on dialysis, the maximum dose should not exceed 5 mg.
Men with severe liver disease should not take tadalafil. Men with mild to moderate liver disease should not exceed tadalafil dose of 10 mg once daily.

Avanafil (Stendra)
Avanafil was recently FDA approved to treat erectile dysfunction. Common side effects may include headache, flushing, sore throat, stuffy and/or runny nose, and back pain. The drug is not recommended for patients with cardiac problems (in the last six months), hypotension or hypertension, unstable angina or congestive heart failure.

What are intracavernosal injections?
Medications can be injected directly into the corpora cavernosa to attain and maintain erections. Medications such as papaverine hydrochloride, phentolamine, and prostaglandin E1 (alprostadil) can be used alone or in combinations to attain erections. Combining small amounts of each drug is preferred over using a single drug because of increased efficacy and fewer side effects. Even though such injections can be effective in the management of erectile dysfunction (success rate of around 80%), they are not widely used because of their potential complications. These injections are painful, can cause scarring of the penis, and lead to a higher risk of developing priapism.

What are intraurethral suppositories?
Prostaglandin E1 (intraurethral alprostadil or MUSE) can be inserted in a pellet (suppository) form into the urethra to attain erections. This technique also is not popular because of occasional side effects of pain in the penis and sometimes in the testicles, mild urethral bleeding, dizziness, and vaginal itching in the sex partner. Men also need to remain standing after inserting the pellet in order to increase blood flow to the penis, and it may take 15-30 minutes to attain an erection. Prostaglandin can cause uterine contractions and should not be used by men having intercourse with pregnant women unless condoms or other barrier devices are used. This drug is now rarely used since the introduction of oral medications, however, it may play a role in management of erectile dysfunction in those who are not a candidate for oral PDE5 medications.

How effective is testosterone in treating erectile dysfunction? In patients with hypogonadism, testosterone treatment can improve libido and erectile dysfunction, but the response of erectile dysfunction in men with hypogonadism to testosterone is not complete; many men still may need additional oral medications such as sildenafil, vardenafil, or tadalafil.

In men 40 years of age or older, a breast examination, digital examination of the prostate, and a PSA level (prostate specific antigen) blood test should be done to exclude breast and prostate cancer before starting testosterone treatment since testosterone can aggravate breast and prostate cancers. Patients who have breast and prostate cancers or are suspected of having them should not use testosterone.

Blood testosterone levels can be measured to detect deficiency. Although, there is no clear-cut testosterone level to define hypogonadism, levels lower than 250 nanograms per deciliter are considered low, and levels of greater than 350 nanograms per deciliter are considered normal. Testosterone levels in between these numbers may be labeled indeterminate.

Certain medications can alter the gonadal function, including thiazide diuretics, some seizure medications, long-acting oral opiate pain medications, antipsychotic medications, and oral steroids.

Can a penis pump (vacuum device) help erectile dysfunction?
Mechanical vacuum devices cause an erection by creating a vacuum around the penis that draws blood into the penis, engorging it, and expanding it. The devices have three components:

a plastic cylinder, in which the penis is placed;
a pump, which draws air out of the cylinder;
an elastic band, which is placed around the base of the penis, to maintain the erection after the cylinder is removed and during intercourse by preventing blood from flowing back into the body (see figure 2).

One variation of the vacuum device involves a semi-rigid rubber sheath that is placed on the penis and remains there after attaining erection and during intercourse.
Picture of vacuum-constrictor device for erectile dysfunction (ED) Picture of a penis pump for erectile dysfunction (ED); SOURCE: NIH

Can low testosterone level be replaced?
Because of potential adverse effects and complex metabolism, the use of testosterone replacement therapy (TRT) is limited to men with symptoms of erectile dysfunction and a testosterone level of less than 200 nanograms per deciliter. Preparations available in the U.S. are topical, injectable, and transbuccal (placing inside mouth between the cheek and upper gum) testosterone. Oral preparations are not available in the U.S.

Common side effects of testosterone replacement therapy include local irritations, prostate enlargement, breast tissue enlargement, aggravation of breast and prostate cancers, depression, elevation of red blood cell count (polycythemia), or worsening of congestive heart failure.

What about psychological therapy for erectile dysfunction?
Experts often treat psychologically based impotence using techniques that decrease anxiety associated with intercourse. The patient's partner can help apply the techniques, which include gradual development of intimacy and stimulation. Such techniques also can help relieve anxiety when physical impotence is being treated. If these simple behavioral methods at home are ineffective, referral to a sex counselor may be advised.

Surgery for erectile dysfunction
Surgery for erectile dysfunction may have the following as its goal:

To implant a device that causes the penis to become erect
To reconstruct arteries in order to increase the flow of blood to the penis
To block veins that drain blood from the penis
Implantable devices, known as prostheses, can allow erections in many men with impotence.

Malleable implants usually consist of paired rods, which are inserted surgically into the corpora cavernosa, the twin chambers exercising the length of the penis. The user manually adjusts the position of the penis and, therefore, the rods. Adjustment does not affect the width or length of the penis.

Inflatable implants consist of paired cylinders, which are surgically inserted inside the penis and can be expanded using pressurized fluid (see figure 3). Tubes connect the cylinders to a fluid reservoir and pump, which also are surgically implanted. The patient inflates the cylinders by pressing on the small pump, located under the skin in the scrotum. Inflatable implants can expand the length and width of the penis somewhat. They also leave the penis in a more natural state when not inflated.

Possible problems with prostheses include mechanical breakdown and infection. Mechanical problems have diminished in recent years because of technological advances.

Picture of an inflatable implant for erectile dysfunction
Picture of an inflatable implant for erectile dysfunction; SOURCE: NIH

Surgery to repair arteries (penile arterial reconstructive surgery) can reduce impotence caused by obstructions that block the flow of blood to the penis. The best candidates for such surgery are young men with discrete blockage of an artery because of a physical injury to the pubic area or a fracture of the pelvis. The procedure is less successful in older men with widespread blockage of arteries.

Can over-the-counter (OTC) and/or natural or home remedies treat erectile dysfunction?
The U.S. FDA (Food and Drug Administration) has a list of 29 OTC products that claim to treat erectile dysfunction. These are recommended to be avoided because many contain harmful ingredients. Other natural or herbal remedies such as DHEA, L-arginine, ginseng, and yohimbe are supplements that have been used but have not been proven to be safe and effective according to some researchers. Before using such compounds, individuals should consult their doctor. Acupuncture, according to some experts, has not been definitively shown to effectively treat erectile dysfunction.

Is it possible to prevent erectile dysfunction?
Prevention of some of the causes that contribute to the development of erectile dysfunction can decrease the chances of developing the problem. For example, if a person decreases their chances of developing diabetes, heart disease, and hypertension, they will decrease their chances of developing erectile dysfunction. Other things like stopping smoking, eating a healthy diet (heart-healthy with adequate vitamin intake), and exercising daily may also reduce a person's risk.

What is the prognosis for erectile dysfunction?
The prognosis for erectile dysfunction is quite variable among individuals. Some people who seek help (medical and/or psychological) can get very good outcomes, while others may have little or no improvements. For example, about 60% of men treated with appropriate medication report improvement in erectile dysfunction. Those individuals who do not seek help usually do not improve and may develop worsening symptoms. In some individuals who require surgery or other interventions, the prognosis is variable and may depend on how the individual responds to treatments.

What research is being done for erectile dysfunction?
Combination therapy for the treatment of erectile dysfunction has been under investigation. Most of these studies have been small trials, and long-term data regarding their effectiveness and safety are lacking. However, with thorough evaluation and counseling, there may be a use for combination therapy for certain individuals with ED.

Melanocortin receptor agonists are a new set of medications being developed in the field of erectile dysfunction. Their action is on the nervous system rather than the vascular system. PT-141 is a nasal preparation which appears to be effective alone or in combination with PDE5 inhibitors. The main side effects include flushing and nausea. These drugs are currently not approved for commercial use.