For the new study, researchers reviewed the medical records of about 277,000 Tennessee Medicaid enrollees for the years 1990 to 2005. Of them, about 46,000 were taking atypical antipsychotic drugs and 44,000 were taking typical antipsychotic drugs. About 187,000 weren't taking any of the drugs. Patients ranged in age from 30 to 74 years; the average age was about 46.

The growing use of antipsychotic drugs has sparked widespread debate in the medical world. In November, 2007, a panel of outside advisers urged the Food and Drug Administration to discourage doctors from prescribing the drugs for children. Meanwhile, Connecticut, Arkansas and other states have sued a number of drug makers, alleging that they marketed such drugs for uses not authorized by the FDA and didn't adequately disclose potential side effects, such as weight gain and diabetes.

One of the FDA's primary functions is to approve drugs for specific uses. Doctors can prescribe them for other treatments, however, but drug makers can't promote them for unapproved uses.

Traditional, or typical, antipsychotic drugs like chlorpromazine, known by the brand name Thorazine, have been used to treat conditions such as schizophrenia since the 1950s. The side effects include involuntary tremors and tics, which can be irreversible. Research have also linked them to sudden cardiac death, an abrupt and unexpected loss of heart function.

The atypical drugs were first introduced in 1989, and were said to cause fewer involuntary-movement problems and be much safer. But in recent years, research has brought that view into question.

References
(To view, roll mouse over the "References" heading; to hide, click on the heading)