Revatio is a drug that is identical to Viagra 100 mg in composition and action. The main difference between them is that this medicine is produced in India according to the classic recipe and does not have a brand markup. Viagra is a brand name, and this unfairly raises the price of the drug. For this reason, Revatio is much cheaper. There is no patent on this drug, so you can buy it freely and OTC. However, buying a drug without a prescription requires from the buyer, the self-analysis of his health state is to avoid the possible risks.
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