Viagra (sildenafil citrate) is by far the most widely used treatment for erectile dysfunction. In the United States, more than 5 million men have used it to improve their sexual function. Doctors in the United States have prescribed it more than 16 million times. And it is available in more than 90 countries worldwide.

     Sildenafil citrate is a prescription medication, so you'll need to talk to your health care provider to find out if it's right for you. Be sure to ask your health care provider if your heart is healthy enough to handle the extra strain of sexual activity. If you have chest pains, dizziness, or nausea during sex, stop and immediately tell your health care provider. Remember to protect yourself and your partner from sexually transmitted diseases.

With viagra, the most common side effects are headache, facial flushing, and upset stomach. It may also briefly cause bluish or blurred vision, or sensitivity to light. In the rare event of an erection lasting more than 4 hours, seek immediate medical help. Remember to protect yourself and your partner from sexually transmitted diseases.

     Viagra, chemically known as sildenafil citrate is useful in producing erections by the following mechanism. When there is sexual stimulation, viagra causes smooth muscle relaxation and inflow of blood to the penis. This results in an erection and “improves performance”.

    People who take nitrates for relief of chest pain should NOT take viagra because it can cause dangerous and life-threatening fall in blood pressure levels. Also if patients have hypersensitivity to any of the ingredients of the drug, they should avoid it.

    Patients who have suffered a heart attack (myocardial infarction), patients having blood pressure less than 90/50 or more than 170/110, cardiac failure patients, people with deformities of penis, leukemics, patients suffering from sickle cell anemia and multiple myeloma

    This is the consistent disability to obtain or maintain an erection for satisfactory sexual reactions. This has replaced the earlier term impotence, which was in use.

Step one – stabilize general condition of the patient. Step two – treat correctable causes Step three – initiate specific therapy – oral sildenafil, transurethral alprostadil, injectable alprostadil, and use of vacuum devices. Step four – penile implants or vascular reconstruction