The prescription of antipsychotic medications for children and adolescents in the US increased nearly 6-fold between 1993 and 2002, according to survey results.

The US Food and Drug Administration has approved only three antipsychotic drugs – haloperidol, thioridazine hydrochloride and pimozide — for use in patients younger than 18 years, but most of the prescriptions written were for newer medications.

“What was most striking is that nearly one in five — 18 percent — of visits to psychiatrists by young people resulted in their being prescribed an antipsychotic medication,” lead investigator Dr. Mark Olfson told Reuters Health.

Interest in this issue followed “earlier studies that reported significant increases in the use of antipsychotics by young people within the Medicaid population,” the researcher added. “We wanted to find out if this was a general trend that more broadly affects the mental health care of youths in the US.”

Olfson, from Columbia University in New York City, and his associates therefore evaluated data from the National Ambulatory Medical Care Survey. Their findings appear in the Archives of General Psychiatry.

The data indicate that “there is a gap between what has been learned in carefully controlled studies and what is actually occurring in practice,” the researcher noted.

Approximately 90 percent of antipsychotics prescribed were for the second-generation drugs — clozapine, risperidone, olanzapine, and quetiapine. None of these drugs are approved for treating adolescents or children.

The researchers note that these drugs were prescribed primarily for disruptive behavior disorders (37.8 percent), mood disorders (31.8 percent), or pervasive developmental disorders or mental retardation (17.3 percent). Only 14.2 percent were prescribed for psychotic disorders.

“It is my guess,” Olfson said, that the “water cooler effect,” in which “physicians learn from one another informally” during discussions or attendance at professional meetings, “has probably contributed to the dissemination of these kinds of prescribing practices.”

A major concern, Olfson said “is that we don’t know enough about the metabolic effects of newer antipsychotics, particularly the long-term effects in young people.”

Source: Archives of General Psychiatry, June 2006.