An increasing number of U.S. adults are being prescribed combinations of antidepressants and antipsychotic medications, according to a report in the January issue of Archives of General Psychiatry.
In some clinical situations, evidence suggests that more than one psychotropic (affecting the brain or mind) medication may be beneficial, according to background information in the article. For instance, a patient with depression who does not respond to one medication alone might require a second antidepressant, or an individual who has depression with psychotic features might respond to a combination of an antidepressant and an antipsychotic. "In routine psychiatric practice, however, patients often receive psychiatric medication combinations that are not well supported by controlled clinical trials," the authors write.
To examine patterns and trends in psychotropic polypharmacy—or the prescription of more than one psychiatric medication—Ramin Mojtabai, M.D., Ph.D., M.P.H., of Bloomberg School of Public Health, Johns Hopkins University, Baltimore, and Mark Olfson, M.D., M.P.H., of Columbia University Medical Center and the New York State Psychiatric Institute, New York, analyzed data collected from a national sample of office-based psychiatry practices. The number of medications prescribed and specific medication combinations were assessed from a total of 13,079 office visits to psychiatrists by adults (18 years or older) between 1996 and 2006.
Overall, there was an increase in the number of psychotropic medications prescribed during office visits. Between 1996 to 1997 and 2005 to 2006, the percentage of visits at which two or more medications were prescribed increased from 42.6 percent to 59.8 percent and the percentage of visits at which three or more medications were prescribed increased from 16.9 percent to 33.2 percent. In addition, the median (midpoint) number of medications prescribed at each visit increased from one to two (an average increase of 40.1 percent).
"The increasing trend of psychotropic polypharmacy was mostly similar across visits by different patient groups and persisted after controlling for background characteristics," the authors write. Combinations of antidepressants with sedative-hypnotics were the most common medication combinations overall (23.1 percent), followed by combinations of antidepressants with antipsychotics (12.9 percent) and combinations of two types of antidepressants (12.6 percent).
"While the evidence for added benefit of antipsychotic polypharmacy is limited, there is growing evidence regarding the increased adverse effects associated with such combinations," the authors write. For example, some combinations have resulted in increases in body weight and total cholesterol level, whereas others may be associated with an increase in fasting blood glucose level.
"Because scant data exist to support the efficacy of some of the most common medication combinations, such as antipsychotic combinations or combinations of antidepressants and antipsychotics, prudence suggests that renewed clinical efforts should be made to limit the use of these combinations to clearly justifiable circumstances," the authors conclude. "At the same time, a new generation of research is needed to assess the efficacy, effectiveness and safety of common concomitant medication regimens, especially in patients with multiple disorders or monotherapy-refractory conditions."
Arch Gen Psychiatry. 2010;67:26-36