In the U.S. Viagra, the anti-impotence pill sells for less than $10 per pill. Only Thailand has approved local sales of the prescription medicine, so men in the rest of Asia are paying up to $80 apiece for illegal imports while waiting for their governments to grant their approval. There is black market in India too. But prospective customers there can expect a local version that promises to be as effective, but not as expensive, as the real thing. Orchid Chemicals and Pharmaceuticals of Madras and Cipla of Mumbai have patented processes to make sildenfil citrate, Viagra's active ingredient.