Viagra is a well known drug which is used in management and treatment of erectile dysfunction. Numerous studies have shown that Viagra expresses a powerful therapeutic effect in more then 80% of men with erectile dysfunction.

Although it is thought that Viagra is nearly all powerful patients must understand that not everybody may use it. In a large number of patients with cardiovascular disease the drug is contraindicated. Another issue is intake of nitrates. Viagra should never be used together with nitrate drugs as life threatening decrease in blood pressure may occur.

Over conditions in which Viagra must be taken with caution include: liver disease, vision impairment, anemia, leukemia, cancer and cavernosal fibrosis. A competent health care professional will always prescribe you the dosage or contradict use of the drug based on age, condition and other medications used. The recommended normal dosage for Viagra or its active ingredient Sildenafil Citrate is 50 mg - 30 minutes prior to the intercourse to reach the best effect.

In elderly patient aged over 65 treatment with Viagra should be carefully considered. And the lowest does of the preparation may be needed Viagra - 25 mg to manage erectile dysfunction. In such patients constant monitoring of vital stats is also required.

As any other drug Viagra may cause certain side effects. Among them are: headache, allergic reaction, vision impairment, flushing, urogenital infections. However in most cases Viagra is well tolerated and is currently the drug of choice for many doctors that treat patients with ED.