Despite the risks involved in the practice, an increasing number of people are privately importing foreign drugs that have yet to gain official approval in Japan. The latest product to come into the limelight is Viagra, a pill to treat impotence that went on sale in the United States in April. It has been wildly popular even among men who have no sexual dysfunction but rave about its ability to enhance sexual potency. About 2 million men are said to have tried it. The Viagra craze has reached far beyond the United States into countries that have not approved the drug for sale, which includes Japan, where travel agencies have set up "Viagra tours."