Examples: Avodart, Proscar

How It Works

5-alpha reductase inhibitors interfere with the effect of certain male hormones (androgens) on the prostate. This slows the growth of the prostate and can even cause it to become smaller, which may help improve the symptoms of benign prostatic hyperplasia (BPH).

But since prostate size does not always correspond to the severity of a man’s symptoms, these medicines will not give satisfactory results in every case.

When you stop taking the medicine, symptoms usually return.

What To Think About

5-alpha reductase inhibitors reduce the size of the prostate. But since a reduction in size does not always bring about symptom relief, these medicines will not give satisfactory results in every case. When you stop taking the medicine, symptoms usually return.

5-alpha reductase inhibitors lower prostate-specific antigen (PSA) levels. Because PSA levels are used to detect early-stage prostate cancer, men interested in taking a 5-alpha reductase inhibitor might consider the following:

• Most experts suggest that men be checked for the presence of prostate cancer (using the PSA test and a digital rectal exam) before taking 5-alpha reductase inhibitors.
• Follow-up PSA levels that have not decreased by approximately 50% after 6 months of taking a 5-alpha reductase inhibitor may indicate a need for further testing for prostate cancer.
• PSA levels above 2 ng/mL (nanograms per milliliter) during 5-alpha reductase inhibitor treatment may indicate a need for further testing for prostate cancer.

5-alpha reductase inhibitors may be less effective than alpha-blockers in relieving symptoms.

5-alpha reductase inhibitors are not recommended for treatment of BPH symptoms in men without an enlarged prostate.

The medicine must be taken for the rest of your life to prevent the symptoms from returning.

This medicine should not be used by men who plan to father a child because of the small chance that the medicine could cause a birth defect. Women who are pregnant or might become pregnant should not handle broken or crushed tablets of finasteride or dutasteride.

Viagra relaxes muscles and increases blood flow to particular areas of the body.

Sildenafil under the name Viagra is used to treat erectile dysfunction (impotence) in men. Another brand of sildenafil is Revatio, which is used to treat pulmonary arterial hypertension and improve exercise capacity in men and women.

Do not take Viagra if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, and others), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket). Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite (“poppers”). Taking Viagra with a nitrate medicine can cause a serious decrease in blood pressure, leading to fainting, stroke, or heart attack.

Before taking Viagra, tell your doctor if you are allergic to any drugs, or if you have:

• heart disease or heart rhythm problems;
• a recent history (in the past 6 months) of a heart attack, stroke, or heart rhythm disorder;
• congestive heart failure;
• high or low blood pressure;
• coronary artery disease;
• liver disease;
• kidney disease;
• a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia;
• a bleeding disorder such as hemophilia;
• a stomach ulcer;
• retinitis pigmentosa (an inherited condition of the eye);
• a physical deformity of the penis (such as Peyronie’s disease); or
• if you have been told you should not have sexual intercourse for health reasons.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take Viagra.

Viagra can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking Viagra, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoke or are over 50 years old. It is not clear whether Viagra is the actual cause of vision loss. Stop using Viagra and get emergency medical help if you have sudden vision loss.

Viagra is usually taken only when needed, 30 minutes to 1 hour before sexual activity. You may take it up to 4 hours before sexual activity. Do not take Viagra more than once per day.

Viagra can help you have an erection when sexual stimulation occurs. An erection will not occur just by taking a pill. Follow your doctor’s instructions.

During sexual activity, if you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw, stop and call your doctor right away. You could be having a serious side effect of Viagra. Store this medication at room temperature away from moisture and heat.

Seek emergency medical attention if you think you have used too much of Viagra. Overdose symptoms may include chest pain, nausea, irregular heartbeat, and feeling light-headed or fainting.

Avoid drinking alcohol, which can increase some of the side effects of Viagra. Avoid using other medicines to treat impotence, such as alprostadil (Caverject, Muse, Edex) or yohimbine (Yocon, Yodoxin, others), without first talking to your doctor.

Stop using Viagra and call your doctor at once if you have any of these serious side effects:

• sudden vision loss;
• ringing in your ears, or sudden hearing loss;
• chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
• irregular heartbeat;
• swelling in your hands, ankles, or feet;
• shortness of breath;
• vision changes;
• feeling light-headed, fainting; or
• penis erection that is painful or lasts 4 hours or longer.

Less serious side effects may include:

• warmth or redness in your face, neck, or chest;
• stuffy nose;
• headache;
• upset stomach; or
• back pain.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect.

You can get more information about Viagra here >>

Levitra is an oral drug for male impotence, also known as erectile dysfunction (ED).

Levitra is a phosphodiesterase inhibitor. It works by helping to increase blood flow into the penis during sexual stimulation. This helps you to achieve and maintain an erection.

Levitra causes erections only during sexual excitement. It does not work in the absence of arousal and does not increase sexual desire.

Take one Levitra tablet about one hour before sexual activity, with or without food.

Take Levitra only before sexual activity, but no more than once a day. Do not take two doses at once.

Store Levitra at room temperature.

Do not take Levitra if you are also using a nitrate drug for chest pain or heart problems. Levitra with a nitrate medicine can cause a serious decrease in blood pressure, leading to fainting, stroke, or heart attack.

Levitra can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking Levitra, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoke or are over 50 years old. It is not clear whether Levitra is the actual cause of vision loss.

Stop using Levitra and get emergency medical help if you have sudden vision loss.

Before taking Levitra, tell your doctor if you are allergic to any drugs, or you have:

• heart disease or heart rhythm problems;
• a recent history (in the past 6 months) of a heart attack, angina (chest pain), or congestive heart failure;
• a recent history of stroke or blood clots;
• a personal or family history of “Long QT syndrome”;
• high or low blood pressure;
• liver disease;
• kidney disease (or if you are on dialysis);
• a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia;
• a bleeding disorder such as hemophilia;
• a stomach ulcer;
• retinitis pigmentosa (an inherited condition of the eye);
• a physical deformity of the penis (such as Peyronie’s disease); or
• if you have been told you should not have sexual intercourse for health reasons.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take Levitra.

Seek emergency medical attention if you think you have used too much of Levitra. Overdose symptoms may include back pain, muscle pain, or vision problems.

Avoid drinking alcohol, which can increase some of the side effects of Levitra.

Grapefruit and grapefruit juice may interact with Levitra. Discuss the use of grapefruit products with your doctor. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor.

Do not use any other drug to treat impotence, such as alprostadil (Caverject, Muse, Edex) or yohimbine (Yocon, Yodoxin, others), unless your doctor tells you to.

Stop using Levitra and call your doctor at once if you have any of these serious side effects:

• sudden vision loss;
• ringing in your ears, or sudden hearing loss;
• chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
• irregular heartbeat;
• swelling in your hands, ankles, or feet;
• shortness of breath;
• vision changes;
• feeling light-headed, fainting; or
• penis erection that is painful or lasts 4 hours or longer.

Less serious side effects may include:

• warmth or redness in your face, neck, or chest;
• stuffy nose;
• headache;
• upset stomach; or
• back pain.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect.

Vardenafil is available with a prescription under the brand name Levitra.

You may buy/order Levitra (Vardenafil) online here.

Cialis is an oral drug for male impotence, also known as erectile dysfunction (ED). It works by dilating blood vessels in the penis, allowing the inflow of blood needed for an erection. Cialis relaxes muscles and increases blood flow to particular areas of the body.

Cialis causes erections only during sexual excitement. It does not work in the absence of arousal and does not increase sexual desire.

Do not take Cialis if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, and others), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket). Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite (“poppers”). Taking Cialis with a nitrate medicine can cause a serious decrease in blood pressure, leading to fainting, stroke, or heart attack.

Do not take Cialis more than once a day. Allow 24 hours to pass between doses.

Contact your doctor or seek emergency medical attention if your erection is painful or lasts longer than 4 hours. A prolonged erection (priapism) can damage the penis.

Cialis can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking Cialis, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoke or are over 50 years old. It is not clear whether this medication is the actual cause of vision loss.

Before taking Cialis, tell your doctor if you are allergic to any drugs, or if you have:

• heart disease or heart rhythm problems;
• a recent history a heart attack (within the past 90 days);
• a recent history of stroke or congestive heart failure (within the past 6 months);
• angina (chest pain);
• high or low blood pressure;
• liver disease;
• kidney disease (or if you are on dialysis);
• a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia;
• a bleeding disorder such as hemophilia;
• a stomach ulcer;
• retinitis pigmentosa (an inherited condition of the eye);
• a physical deformity of the penis (such as Peyronie’s disease); or
• if you have been told you should not have sexual intercourse for health reasons.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take Cialis.

Take one Cialis tablet before sexual activity, with or without food. The best time to take Cialis depends on how and when the drug works for you, but some men are able to have an erection 30 minutes after taking it. Others are able to wait up to 36 hours after taking Cialis before engaging in sexual activity.

Take Cialis only before sexual activity, but no more than once a day. Do not take two doses at once.

Seek emergency medical attention if you think you have used too much of Cialis. Overdose symptoms may include chest pain, nausea, irregular heartbeat, and feeling light-headed or fainting.

Store Cialis at room temperature.

Avoid drinking alcohol, which can increase some of the side effects of Cialis.

Avoid using other medicines to treat impotence, such as alprostadil (Caverject, Muse, Edex) or yohimbine (Yocon, Yodoxin, others), without first talking to your doctor.

Stop using Cialis and call your doctor at once if you have any of these serious side effects:

• sudden vision loss;
• ringing in your ears, or sudden hearing loss;
• chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
• irregular heartbeat;
• swelling in your hands, ankles, or feet;
• shortness of breath;
• vision changes;
• feeling light-headed, fainting; or
• penis erection that is painful or lasts 4 hours or longer.

Less serious side effects may include:

• warmth or redness in your face, neck, or chest;
• stuffy nose;
• headache;
• upset stomach; or
• back pain.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect.

You may buy/order Cialis (Tadalafil) online here.

In typical “sky-is-falling” style, some news items trumpeted this possible relationship to make it appear that almost everyone who took Viagra was at risk for serious damage to their eyes. The reality is quite different.

Viagra and the other PDE5 inhibitors, Levitra and Cialis, work by selectively inhibiting the action of a specific enzyme, PDE5, found in all the body’s vascular tissues (blood vessels). To some extent, these drugs also selectively inhibit another enzyme in the same family, PDE6, which tends to be located in the rod and cone receptors in the eye.

This is the reason for occasional mild to moderate vision side effects in men taking a PDE5. These effects, such as blue-tinged vision, lights that appear too bright, blurry vision, and difficulties with color discrimination, are almost always mild and usually disappear rather quickly.

Careful studies in people with and without eye disease have shown repeatedly that Viagra does not permanently affect visual acuity (sharpness), fields of vision, or sensitivity to visual contrast.

Over several years, isolated case reports in the medical literature have indicated that NAION and other serious visual conditions have been associated with PDE5 treatment. These reports represent the experiences of a handful of the more than 27 million men who’ve taken a PDE5 drug. At least some of these reported cases may be due to the fact that men who suffer from ED also tend to have multiple risk factors for the vascular problems that make a person vulnerable to NAION.

To date, there is no compelling evidence that taking Viagra places anyone at increased risk for NAION or related conditions affecting the retina or other important structures of the eye. Once again, the real story on this complex subject is not as simple as some news headlines.

The presence of ED can often be one of the earliest signs of problems in endothelial function that may later progress to heart disease. In such cases of ED, the vascular endothelium loses its capacity to form nitric oxide, which is necessary to dilate the blood vessels in the penis that cause an erection.

If this hypothesis is correct, then a drug designed to treat this damaged vascular endothelium, such as a statin, should help men with ED who do not respond to treatment with Viagra.

One small but promising study involved men who previously failed treatment with Viagra alone. The men were given 80 mg daily of the statin Lipitor or a placebo. Both groups also received 100 mg tablets of Viagra to use for sexual purposes. After 12 weeks, the Viagra-plus-Lipitor group had statistically significant improvement in erectile function, while the placebo group showed no such improvement.

Although the number of men in the study was small, the results nonetheless are promising enough for the authors to call for larger trials to be done.

Treatment of erectile dysfunction is much easier now, thanks to a class of drugs called phosphodiesterase-5 (PDE-5) inhibitors. The medications — sildenafil (Viagra), vardenafil (Levitra) and tadalafil (Cialis) — all improve erectile function in the same basic way, but they differ in how quickly they take effect and how long their effects last.

How Viagra, Levitra and Cialis work

Viagra, Levitra and Cialis prevent the breakdown of nitric oxide, a chemical messenger that promotes relaxation and opening of the blood vessels that supply erectile tissue in the penis. Under the influence of nitric oxide, these vessels expand and stay dilated. Increased blood flow makes erectile tissue swell and compress the veins that carry blood out of the penis, resulting in a full erection.

PDE-5 inhibitors do not automatically trigger erections. Sexual stimulation also is needed to start the whole process. The medications enable a more complete response to sexual stimulation.

Many clinical trials have shown that PDE-5 inhibitors improve erectile function regardless of the underlying cause or causes. Viagra, Levitra and Cialis increase the number and quality of erections and sexual experiences in men with erectile dysfunction due to arteriosclerosis, diabetes, spinal cord injury, depression or the aftereffects of prostate cancer surgery.

Similarities and differences

The drugs have slightly different chemical compositions that affect how quickly they work and wear off. Other distinctions — for example, which drug may be best for men of different ages or with different medical conditions — aren’t known. No study has directly compared these three medications.

Several factors may affect your choice of medication, including how well your body responds to one drug over another and how long you want the effects of each dose to last. Talk to your doctor about your options and personal preferences to help decide which one of these medications might work for you.

Not safe for everyone

Although these medications can help many people, not all men can safely take them. PDE-5 inhibitors may worsen certain medical conditions and interact with a number of drugs. Erectile dysfunction medications are dangerous when used with nitrate medications, such as nitroglycerin (Nitro-Dur, others), often prescribed to prevent or treat acute angina (chest pain due to coronary artery disease). Both types of medication dilate blood vessels, and their combined effects can cause dizziness, low blood pressure and loss of consciousness.

In rare cases, men using PDE-5 inhibitors have suffered permanent, total vision loss due to nonarteritic anterior ischemic optic neuropathy (NAION). Because NAION and erectile dysfunction share many of the same risk factors, it’s unclear whether the drug or an underlying condition is responsible. If you’re considering an erectile dysfunction drug but have a retinal disorder, such as diabetic retinopathy, see your eye doctor first.

Realistic expectations

Occasional erectile dysfunction is a common problem, particularly as men age. Medication won’t make you feel like you’re 20 again, but it can help you achieve satisfying sexual relations more often. Be willing to work with your doctor to find which medication and dosage is best for you.

Brand name — Chemical name
Viagra — sildenafil citrate
Levitra — vardenafil
Cialis — tadalafil

Phosphodiesterase-5 inhibitors (PDE-5 inhibitors) are taken at least an hour before you plan to be sexually active. PDE-5 inhibitors will result in an erection only if you are sexually stimulated.

How It Works

During an erection, blood fills tissue in the penis, causing it to enlarge and become stiff. The PDE-5 inhibitors relax smooth muscle, allowing the penis to fill with blood.

Stimulation of the penis is necessary for Levitra and Cialis to work; Viagra can produce a spontaneous erection in those men for whom it is effective.

Why It Is Used

PDE-5 inhibitors can be used when an erection problem (erectile dysfunction) is caused by:

• Diabetes.
• High blood pressure.
• Spinal cord injury or other problems affecting nerve function.
• Prostate surgery.
• Side effects of medications.
• Emotional or psychological causes.

How Well It Works

PDE-5 inhibitors are effective treatment for erection problems. A review of trials has shown that 83% of men with erection problems who used Viagra had improved erections that allowed them to have intercourse. Initial studies show Levitra and Cialis have rates of success similar to those of Viagra. Viagra has been studied extensively and used by millions of men; its side effects and long-term effects are well recognized. Levitra and Cialis are new drugs in which long-term effects have not been studied.

PDE-5 inhibitors should be taken at least an hour before you plan to be sexually active.

One study found that Cialis, called “the weekend pill,” enhanced the ability to have erections for 24 to 36 hours after taking it. Viagra and Levitra usually enable a man to get an erection at any time for 4 or more hours after taking it.

Viagra does not work as well as it would otherwise if you eat a high-fat meal around the time you take it, so many doctors recommend you take it on an empty stomach. Levitra may be slightly less effective if you eat a high-fat meal, but a moderate-fat meal does not reduce its effectiveness; Cialis works without regard to what you eat.

Side Effects

Do not take PDE-5 inhibitors if you are taking any medication that contains nitrates, such as nitroglycerin. This combination can lower blood pressure dangerously, possibly leading to a stroke, a heart attack, or death. If you are taking a medication called an alpha-blocker—used to treat high blood pressure or an enlarged prostate—check with your health professional before you take a PDE-5 medication.

Other side effects are fairly uncommon when taking PDE-5 inhibitors. They include:

• Headache.
• Skin flushing.
• Indigestion.
• Nasal congestion.

A few men find that PDE-5 inhibitors affect their vision for a few hours after taking it, usually by causing a slight bluish tinge to their vision. A few men become more sensitive to light. These effects go away in a few hours.

What To Think About

Health experts have debated the use of PDE-5 inhibitors in men with heart disease, because deaths have been reported in men who used Viagra. The 1999 American College of Cardiology/American Heart Association (ACC/AHA) Expert Consensus Document noted that PDE-5 inhibitors may be dangerous for people who: ⁵

• Have coronary artery disease (CAD).
• Have heart failure and low blood pressure.
• Are taking many different drugs for high blood pressure.

However, several studies have reported that some men with heart problems may be able to take PDE-5 inhibitors safely.

• One study found no evidence of increased risk of heart attack or CAD in men who use Viagra.
• Another study in men with CAD reported that Viagra does not lead to heart attack and that heart attacks and other cardiovascular problems reported after taking Viagra may be related more to the physical activity of intercourse than to the medication.
• A study of 35 men found that Viagra is safe for men with moderate heart failure.

Sexual activity is exercise. If you have a heart condition and have not been sexually active for a while, talk with your health professional to make sure you can safely engage in sexual activity.

PDE-5 inhibitors are not prescribed for anyone who may take nitroglycerin in an emergency.

Tell your health professional if you are using PDE-5 inhibitors and are going to have a test for heart disease (such as a stress treadmill test, cardiac catheterization, stress thallium, or stress echocardiography). You should avoid taking PDE-5 inhibitors for 24 to 48 hours before such a test.

When considering PDE-5 inhibitors for erection problems, it is important to include your partner in your discussions.

If you take any medications, discuss PDE-5 inhibitors with your health professional before using them.

PDE-5 inhibitors can be prescribed by any doctor. You do not have to see a doctor who specializes in sexual health. PDE-5 inhibitors are also available on the Internet; if you obtain the medication through this route, you should discuss its use with your doctor.