IT could be months before public hospitals can offer free supplies of the anti-impotence drug Viagra, although it could be on pharmacy shelves by Friday. But doctors said that most impotent men were shy and would rather pay for the drug than go through the public health system. The Hospital Authority, which will govern the prescription of Viagra in public hospitals, said yesterday it might take months for the Government to decide whether to subsidise the drug or make patients pay. Urologist Dr Andrew Yip Wai-chun, a member of the Hospital Authority's taskforce on the use of Viagra, said the decision was a controversial one everywhere. 'In the United States, you have some states choosing to pay for the drug and others opting not to,' Dr Yip said. The SAR provides most medicines for free, but there is strong debate over whether Viagra should be included. Critics point out that impotence is not fatal and that the drug merely improves quality of life. Costs could spiral if patients received it whenever they wanted sex. Yet advocates of free Viagra said there should be no discrimination against sexual disorders. Dr Yip said medical experts, health officials and possibly legislators would discuss the issue, taking public opinion into account. Patients with prescriptions will soon be able to buy the drug in pharmacies for about $100 a tablet. The Hospital Authority has determined patients can receive a prescription of four tablets at their first consultation and up to 10 tablets a month for a maximum four-month treatment period. Dr Yip said that Hong Kong people were shy about discussing sex and more likely to simply pay rather than try to get subsidies. They could then refill their prescriptions as often as necessary without embarrassing follow-up visits to public doctors' offices. In a survey of 1,000 of his patients, Dr Yip found 90 per cent were willing to pay for Viagra.