Use of psychiatric drug combos growing in the U.S.

NEW YORK (Reuters Health) - US adults being treated for mental illness are more likely to be prescribed two or more drugs today than a decade ago.

Although little is known about whether they work or what the long-term side effects might be, psychiatric drug combinations are increasingly being used to treat a wide range of mental illness including anxiety, depression, panic disorder, posttraumatic stress disorder, bipolar disorder and schizophrenia, a report published Monday suggests.

"We have to figure out if these combinations are adding any benefits to patients," Dr. Ramin Mojtabai of the Bloomberg School of Public Health at Johns Hopkins University in Baltimore, Maryland told Reuters Health.

In the first study of its kind, Mojtabai and colleague Dr. Mark Olfson of Columbia University Medical Center and the New York State Psychiatric Institute examined data collected during 13,000 office visits to U.S. psychiatrists between 1996 and 2006.

They focused on the four major classes of psychotropic (brain or mind affecting) medications: antidepressants, antipsychotics, mood stabilizers, and sedatives.

Mojtabai and Olfson found that antidepressants were the most commonly prescribed medications. Prescribing antidepressants with another antidepressant, a sedative or a mood stabilizer were the three most common psychotropic combinations.

During the study period, as more patients were prescribed at least one psychotropic drug, the number of office visits where two or more drugs were prescribed jumped from roughly 43 percent to 60 percent -- a "substantial increase," the authors note in the Archives of General Psychiatry.

Insured women, 45 to 64 years old and on a repeat visit to the psychiatrist, were the most likely to get two or more prescriptions.

Most troubling, Mojtabai told Reuters Health, was the increased practice of combining two antipsychotics, a type of drug most often given to people with schizophrenia. The evidence that antipsychotic combinations are effective is "limited," the authors wrote.

Mojtabai said prescribing practice may have moved ahead of the evidence because new psychotropic drugs don't carry the same side effects as earlier generation drugs.

"Maybe physicians have become less vigilant about, and less concerned about combining medications because the immediate side effects are less pronounced," Mojtabai said.

"The new antipsychotics, for example, have fewer side effects like dry mouth and blurred vision. So, as a result, physicians are less concerned about combining them," he added.

But, as the authors point out in their report, there is "growing evidence regarding the increased adverse effects" associated with psychotropic combinations, including the long-term risk of weight gain, diabetes, or heart trouble.

Mojtabai and Olfson urge the mental health profession to reign in the use of psychotropic combinations pending better evidence of safety and efficacy.

"Continued unabated, the cost increases associated with increased use of these medications may bring on administrative mandates and restrictions on coverage to limit this practice," they warn.

SOURCE: Archives of General Psychiatry, January 2010.