Reports of deaths among men who took the popular impotence pill Viagra have climbed to 16, including seven who died during or after sex - an important reminder that sexual exertion itself can be risky in older men or heart patients.

Doctors say they're cautioning patients about the risks, but that some men just don't care."I've had a lot of patients say, 'If I have to go, that's the way I want to go out,' " said Dr. Ira Sharlip of San Francisco, an adviser on impotence to the American Urological Association.

"I've taken prescriptions out of two patients' hands who lied about (using) nitroglycerin" because they wanted Viagra so badly, said Dr. William Steers, the University of Virginia's urology chairman.

Men who take nitroglycerin or related heart drugs should never take Viagra because the drug mix can cause a deadly decline in blood pressure.

"Men value sexuality over general health," Steers added. "They are going to have this regardless of the consequences."

But just what the consequences are is the question.

The Food and Drug Administration stressed Tuesday that there is no evidence that Viagra itself is to blame for the 16 deaths but posted information about them on its Internet site in response to intense public interest in the drug.

The FDA's Internet address is (www.fda.gov).