Generic Viagra

If you have heart problems severe enough to make sexual activity a danger, you should avoid using Viagra.

Use it cautiously —if at all— if you’ve had a heart attack, stroke, or life-threatening heart irregularities within the past 6 months. Be equally cautious if you have severe high or low blood pressure, heart failure, or unstable angina (crushing heart pain that occurs at any time).

If you take Viagra and develop cardiac symptoms (for example, dizziness, nausea, and chest pain) during sexual activity, do not continue. Alert your doctor to the problem as soon as possible.

If you have a condition that might result in long-lasting erections, such as sickle cell anemia, multiple myeloma (a disease of the bone marrow), or leukemia, use Viagra with caution. Also use cautiously if you have a genital problem or deformity such as Peyronie’s disease. If an erection lasts more than 4 hours, seek treatment immediately. Permanent damage and impotence could result.

If you have a bleeding disorder, a stomach ulcer, or the inherited eye condition known as retinitis pigmentosa, use this medication with caution. Its safety under these circumstances has not yet been studied.

Remember that Viagra offers no protection from transmission of sexually transmitted diseases, such as HIV, the virus that causes AIDS.

This drug is not for use by women. Its effects during pregnancy have not been studied.

As many as half of the Viagra anti-impotence pills sold on the Internet could be counterfeit, say U.K. scientists.

Dr Nic Wilson of the School of Pharmacy, University of London, analysed samples of Viagra sold on the Web and found that some of the little blue pills contained different components or less of the active ingredient than the top-selling drug made by pharmaceutical giant Pfizer Inc.

“On our initial estimate, around half of those Viagra samples could be counterfeit,” Wilson told the British Pharmaceutical Conference in Manchester this week. Wilson’s work is funded by a university fellowship and she is working in collaboration with the U.K. medicines regulatory agency and Pfizer.

Viagra, which works by allowing more blood-flow to the penis during sexual arousal, is a lifestyle drug along with hair-loss and weight treatments. All are widely available on the Internet and major targets for counterfeiters.

With impotence, or erectile dysfunction (ED), affecting about 152 million men worldwide, there is a huge market for the treatment. It is estimated that half of all men over 40 experience some degree of ED, which increases with age. About 95% of cases can be successfully treated.

The bogus drugs were branded and labelled Viagra and came in identical packaging to the real thing.

Researchers are not sure whether wrong components in the bogus pills are harmful, but at the very least it is highly probable the fakes will not work.

If the counterfeiters get the dose wrong and the bogus pills contain too much of the active ingredient, sildenafil, it could be dangerous.

“Part of the side reaction of the sildenafil is increased heart pressure, so people could get heart attacks,” Wilson’s colleague Professor Tony Moffat said.

“If you go to a site that looks a bit wonky, they are selling it cheap and you’ve got no address or idea where they are based, you are chancing it.”

Wilson and Moffat used a technique called near infrared (NIR) microscopy which provides a more detailed picture of what is in a tablet and its active ingredients to separate the fakes from the real thing.

The researchers tested the technique on known counterfeit Viagra before using it on pills they bought on the Internet. Pills arrived from a variety of countries including Thailand, India and Malta.

Eventually they believe the technology will be able to track the counterfeit products across the world.

In rare instances, men taking PDE5 inhibitors (oral erectile dysfunction medicines, including VIAGRA) reported a sudden decrease or loss of vision. It is not possible to determine whether these events are related directly to these medicines or to other factors. If you experience sudden decrease or loss of vision, stop taking PDE5 inhibitors, including VIAGRA, and call a doctor right away.

Sudden decrease or loss of hearing has been rarely reported in people taking PDE5 inhibitors, including VIAGRA. It is not possible to determine whether these events are related directly to the PDE5 inhibitors or to other factors. If you experience sudden decrease or loss of hearing, stop taking VIAGRA and contact a doctor right away.

If you have prostate problems or high blood pressure for which you take medicines called alpha blockers, your doctor may start you on a lower dose of VIAGRA.

Remember to protect yourself and your partner from sexually transmitted diseases.

The most common side effects of VIAGRA are headache, facial flushing, and upset stomach. Less commonly, bluish vision, blurred vision, or sensitivity to light may briefly occur.