The Expiration Date for Antipsychotic Benefits

Antipsychotic use in bipolar patients after mania resolution may cause weight gain if prolonged

/ Author:  / Reviewed by: Jennifer Gershman, PharmD, CPh

(RxWiki News) After an acute manic episode, bipolar patients are often kept on antipsychotic medications to prevent future episodes. But the potential risks of this practice may outweigh the benefits.

A recent study from Canada found that continuing patients with bipolar disorder (BD) on antipsychotics — in combination with mood stabilizers — for more than six months after mania remission may not prevent future episodes and may also pose some significant health risks.

Because many antipsychotics cause weight gain and metabolic syndrome, the authors of this study said these drugs should not be continued unless the benefits beyond six months can be clearly demonstrated.

BD is a brain disorder that causes large shifts in mood, energy, activity levels and behavior. These shifts can be severe and are different from the normal ups and downs of everyday life.

Patients with BD often cycle through intense emotional states that occur in distinct periods. An overly joyful or excited state is called a manic episode. An extremely sad or hopeless state is called a depressive episode. A mixed episode is a combination of the two.

There are four basic types of BD. Bipolar I disorder is defined by manic or mixed episodes that last at least seven days, or by manic episodes that are so severe that a patient needs immediate medical attention.

For this study, a team of researchers led by Lakshmi N. Yatham, MRCPsych, a professor of psychiatry at the University of British Columbia in Vancouver, looked at 159 patients with bipolar I disorder who were in remission for two to six weeks from an acute manic episode. All of these patients were taking a mood stabilizer (either lithium or valproate) plus an antipsychotic (either risperidone or olanzapine).

These patients were then randomly assigned to discontinue their antipsychotic immediately, after 24 weeks or after 52 weeks.

Dr. Yatham and team found that both the immediate and 24-week group had a 65 percent chance of another episode within one year. The 52-week group had an 82 percent chance. Antipsychotic use was also linked to significantly more weight gain at 52 weeks than at 24 weeks.

This study was published Oct. 13 in the journal Molecular Psychiatry.

The Canadian Institutes of Health Research funded this research. Several study authors disclosed potential conflicts of interest, including ties to pharmaceutical companies that make drugs used in BD treatment.

Review Date: 
December 1, 2015
Last Updated:
December 2, 2015