Some newer antipsychotic medications approved to treat schizophrenia and bipolar disorder are being prescribed to millions of Americans for depression, dementia, and other psychiatric disorders without strong evidence that such off-label uses are effective, according to a new analysis by HHS' Agency for Healthcare Research and Quality
The federally funded comparative effectiveness review of these drugs - called atypical antipsychotics - identified the medications' potential for serious side effects while pointing to an "urgent need" for more research into new treatments for the growing population of dementia patients who display severe agitation.
"This report emphasizes the importance of understanding the risks and benefits of different medicines," said AHRQ Director Carolyn M. Clancy, M.D. "Caution is necessary in the off-label use of atypical antipsychotics, especially when used in the elderly and when the evidence for effectiveness is not good."
Atypical antipsychotics are second-generation medicines designed to cause fewer neurological complications than conventional antipsychotics. They include aripiprazole (sold as Abilify), olanzapine (Zyprexa), quetiapine (Seroquel), risperidone (Risperdal), and ziprasidone (Geodon). Each is approved by the Food and Drug Administration to treat schizophrenia and bipolar disorder, and risperidone is also approved to treat irritability in children ages 5 to 16 who have autism.
Some studies suggest that atypical antipsychotics may help patients with mental health conditions for which there are no FDA-approved alternatives. Risperidone and quetiapine, for example, help certain patients with obsessive-compulsive disorder when used in conjunction with antidepressants. Risperidone and olanzapine improve sleep problems, depression, and other symptoms in men with combat-related post-traumatic stress disorder when used to augment therapy with antidepressants or other psychotropic medications.
Overall, however, researchers found that much of the scientific evidence for off-label use of antipsychotics was of insufficient quality because studies were too small or lacked scientific rigor.
Review authors evaluating the potential benefits and risks of the medications also found strong evidence that atypical antipsychotics can increase chances of adverse events. Some of the drugs increase risks of stroke, tremors, significant weight gain, sedation, and gastrointestinal problems.
The new review was produced by AHRQ's Effective Health Care program. It was authored by AHRQ's Southern California/RAND Evidence-based Practice Center. The center examined 84 published studies on atypical antipsychotics and summarized evidence about several conditions:
Dementia: One analysis showed a small benefit for risperidone and aripiprazole in the treatment of agitation and psychosis. Another suggested olanzapine may help treat psychosis. But a large clinical trial that explored whether risperidone, olanzapine, and quetiapine controlled behavioral disturbances in Alzheimer's patients concluded that the risks of adverse events offset the potential benefits. Overall, analyses identified potential harms as a small increase in the risk of death and increased chances of stroke, neurological problems (such as tremors or muscle contractions), and weight gain.
Depression: For patients who don't benefit from selective serotonin reuptake inhibitors (SSRIs), the supplemental use of atypical antipsychotics was not helpful, according to research. No studies showed the drugs provided a clear benefit for patients with major depressive disorder with psychotic features. Evidence is conflicting for bipolar depression.
Obsessive-Compulsive Disorder: Atypical antipsychotics significantly helped patients who don't respond adequately to SSRI therapy, studies showed. Overall, patients taking the drugs were about 2.7 times as likely to improve as patients taking placebo. The chances of benefiting were best for risperidone and quetiapine.
Post-Traumatic Stress Disorder: Studies of men with combat-related PTSD showed risperidone and olanzapine, when used with antidepressants or other psychotropic medications, improved sleep quality, anxiety, and other symptoms. Studies were inconclusive when measuring benefits for women.
Personality Disorders: For patients with borderline personality disorder, one study suggested olanzapine was more effective than placebo but showed little benefit when used to augment talk therapy. All studies of olanzapine were very small, however, and patients experienced significant weight gain. Two other small trials suggested risperidone may benefit patients with schizotypal personality disorder, and aripiprazole may help patients with borderline personality disorder.
Tourette's Syndrome: Risperidone is more effective than placebo, according to a small body of research. The benefits of ziprasidone are uncertain
Off-label prescribing is a common but relatively understudied practice in health care. A 2001 AHRQ-funded study concluded that about 21 percent of prescribed drug use was for conditions not indicated on the label. Cardiac medications and anticonvulsants were the drugs most commonly used off label. Most off-label use occurs without scientific support, the study said.