By DONALD MACINTYRE

he middle-aged businessman had tried everything, from vitamins to ginseng tonics to testosterone. He had even gulped down a highly touted potion made from powdered pit vipers. Nothing seemed to do the trick. So when he read about a Japanese travel agency that offered "Viagra tours" to Los Angeles, the 53-year-old man, who doesn't want his name published, signed up for the first flight. Upon arrival, he hopped in a taxi and went straight to a hospital near the airport. After a 30-minute check-up he had his prescription for the anti-impotence wonder pills. Back at his hotel room, he flicked on an erotic video and settled back to see if Viagra worked as promised. "It was perfect," the businessman recalls. "I want them to bring it to Japan, fast."

He and others clamoring for the drug at home may be in for a long wait, however. Pfizer is already testing the product in Japan, where an estimated 10 million men suffer some form of impotence. But it will likely take the American drug maker at least three years to win permission to market Viagra from Japan's Health and Welfare Ministry, which is generally slow to approve new drugs. Already, though, a gray market in the blue pills has sprung up. Japanese are ordering Viagra over the Internet, turning to niche importers and anybody with connections in the U.S. (The Internet price: as much as $29 for one 50-mg pill, triple the cost in the U.S.)

These backdoor routes suggest a booming Japanese market in the making, but they also worry local doctors. In some cases, Viagra can cause troubling side-effects. Patients should undergo a thorough examination to check for potentially risky complications like heart trouble and to get proper dosage recommendations, says Dr. Yukie Takimoto, professor of urology at Tokyo's Nihon University. "Japanese tend to take drugs freely, and there's a real threat somebody could take three tablets instead of one," says Takimoto. "It is quite dangerous." So are the small companies peddling Viagra over the Internet and through other channels. Some of them ask customers a few token questions (Do you have heart trouble?) and then fax the responses to a doctor in the U.S., who issues prescriptions--without any individual contact with the patient.

For now, the safest alternative for Japanese men is to travel to a country that sells the pills. (So far, Viagra has been approved for sale only in the U.S. and a handful of other places.) Flight More, which originally flew patients from Japan to L.A., now sends would-be sexual athletes to Hawaii, a destination that is more geared to Japanese tourists. A four-day trip to Honolulu runs $700 with hotel, plus $600 for a consultation, prescription and 30-pill bottle of Viagra. The company says it is getting up to 20 calls a day from men, most of them age 45 to 65.

Japanese who can't afford to travel will have to fall back on the country's flourishing market for health tonics, aphrodisiacs and other "cures" for impotence. A dried pit viper (druggists will grind it for the customer) goes for $57, while a seal's penis costs about $200. An entire deer antler is about $3,450. But one patient has already sworn off such exotic remedies. "I won't be going back to pit vipers," says the businessman who went to L.A. for his Viagra. "No way."

--By Donald Macintyre. With reporting by Hiroko Tashiro/Tokyo

--With Reporting by Hiroko Tashiro /Tokyo