Concerns Mount Over
Viagra's Role in Health Problems
BOSTON (Reuters) - The potential health dangers of the anti-impotence drug Viagra, especially for men with heart problems, may be more extensive than warnings indicate, said researchers in Thursday's New England Journal of Medicine.
Letters published in the journal raised new red flags about Viagra for men with heart trouble and disclosed a possibly fatal lung complication. Another letter tracked bladder infections in women whose spouses said they used the drug.
The popular prescription drug is already known to be hazardous to people with heart disease who take nitrate drugs, such as nitroglycerin tablets.
But Dr. P.K. Shah of the Cedars-Sinai Medical Center in Los Angeles describes two men with heart disease and not taking nitroglycerin who experienced problems after taking Viagra.
One man, 71, had received an implanted defibrillator that delivers a shock if the heart develops an abnormal rhythm. The man had not received a shock for six months.
But after taking Viagra and having sex "he received three shocks, each a few minutes apart." After the third shock, he decided to stop, said Shah. Tests later showed his heart rhythm had been dangerously disrupted.
In the second case, a 52-year-old man whose heart had also been damaged by a heart attack, developed an abnormal heart rhythm after viagra-assisted sex. His heart had to be "shocked" back to normal.
Shah said caution should be exercised in prescribing sildenafil (the generic name for Viagra) to men with a history of abnormal heartbeats.
In another letter, Ira Schwartz and Dr. David McCarthy of the University of Pennsylvania School of Medicine cite a recent study showing that 31 percent of men with heart disease do not get enough oxygen to their heart muscle during sex.
Although 7 percent do not experience any chest pain, 24 percent do, and they might take -- or be given -- nitroglycerin to treat it. They suggest giving an exercise test to potential Viagra users with heart disease to help predict which men may be at risk.
The combination of nitroglycerin and Viagra can cause a deadly drop in blood pressure, as the drug's manufacturer, Pfizer Inc. has warned.
Another letter described a man who developed a fatal lung problem after taking three Viagra tablets over a two-day period. The letter said that Viagra should be used with care in people who might be predisposed to lung bleeding.
A letter from doctors at Newton General Hospital in Covington, Georgia, reported bladder infections in 15 of 100 women whose spouses received Viagra.
"Men treated with sildenafil should be advised to tell their female sexual partners" to drink plenty of water and empty their bladders immediately after sex to avoid an infection, they said.
In a response, a team of researchers who reported on the safety of Viagra in the May 14 issue of the journal said tests showed that the risk of heart attack has been the same whether men received the drug or a placebo. They said there was no evidence Viagra increased the risk of bleeding in the lungs.
Last month, the Food and Drug Administration reported that it had identified at least 69 deaths in the United States that might be linked to Viagra. However, as in the cases cited in the New England Journal of Medicine, a direct cause-and-effect relationship has not been established.
Twelve of the 69 men had taken nitroglycerin or some other nitrate medicine and 18 died during or immediately after sex. Most had some type of risk factor for heart disease.
The FDA cautioned that "an accumulation of adverse event reports does not necessarily indicate that the adverse event was caused by the drug." An underlying disease or some other factor might be responsible in these cases, the FDA said.
During the first four months Viagra was on the market, more than 3.6 million prescriptions for the drug were filled.
By GENE EMERY, Reuters