At first, the psychiatric drug Zyprexa may have saved John Eric Kauffman's life, rescuing him from his hallucinations and other symptoms of acute psychosis.

While taking Zyprexa for five years, Kauffman, who had been a soccer player in high school and had maintained a normal weight into his mid-30s, gained about 80 pounds. He was found dead on March 27 at his apartment in Decatur, Ga., just outside Atlanta.

An autopsy showed that the 41-year-old Kauffman, who was 5 feet 10 inches, weighed 259 pounds when he died. His mother believes that the weight he gained while on Zyprexa contributed to the heart disease that killed him.

Eli Lilly, which makes Zyprexa, said in a statement that Kauffman had other medical conditions that could have led to his death and that "Zyprexa is a lifesaving drug." The company said it was saddened by Kauffman's death.

No one would say Kauffman had an easy life. Like millions of other Americans, he suffered from bipolar disorder, a mental illness characterized by periods of depression and mania that can end with psychotic hallucinations and delusions.

After his final breakdown, in 2000, a hospital in Georgia put Kauffman on Zyprexa, a powerful anti-psychotic drug. Like other medicines Kauffman had taken, the Zyprexa stabilized his moods. For the next five-and-a-half years, his illness remained relatively controlled. But his weight ballooned — a common side effect of Zyprexa.

His mother, Millie Beik, provided information about Kauffman, including medical records, to The New York Times.

For many patients, the side effects of Zyprexa are severe. Connecting them to specific deaths can be difficult, because people with mental illness develop diabetes and heart disease more frequently than other adults. But in 2002, a statistical analysis conducted for Eli Lilly found that compared with an older anti-psychotic drug, Haldol, patients taking Zyprexa would be significantly more likely to develop heart disease, based on the results of a clinical trial comparing the two drugs.

Exactly how many people have died as a result of Zyprexa's side effects, and whether Lilly adequately disclosed those risks, are central issues in the thousands of product-liability lawsuits pending against the company, and in state and federal investigations.

Because Kauffman also smoked heavily for much of his life, and led a sedentary existence in his last years, no one can be sure that the weight he gained while on Zyprexa caused his heart attack.

Zyprexa, taken by about 2 million people worldwide last year, is approved to treat schizophrenia and bipolar disorder. Besides causing severe weight gain, it increases blood sugar and cholesterol in many people who take it, all risk factors for heart disease.