Newer antipsychotic drugs are often prescribed for conditions they aren't approved to treat, with questionable benefits, according to a study.
The medications, known as atypical antipsychotics, include risperidone, sold in the United States as Risperdal, aripiprazole (Abilify), olanzapine (Zyprexa) and quetiapine (Seroquel).
While those drugs have been approved in the United States for a few psychiatric conditions, such as schizophrenia and bipolar disorder, doctors may also prescribe them "off-label" to other patients, including people with substance abuse and eating disorders, typically when they haven't responded to more standard treatments.
"There are several conditions in psychiatry that are pretty difficult to treat," said Alicia Ruelaz Maher from RAND Health in Santa Monica, California, the study author.
"Often in psychiatry we think, if something works for one condition, it could possibly be effective for another one."
People with anxiety or obsessive-compulsive disorder, for example, are often treated with antidepressants known as selective serotonin reuptake inhibitors (SSRIs), but those don't always work.
More and more, doctors are prescribing atypical antipsychotics off-label, experts say.
Yet, Maher said, there's a general lack of evidence on whether atypical antipsychotics can help patients who don't have schizophrenia or bipolar disorder.
She and her colleagues looked at scientific literature and combined data from 162 studies that compared an atypical antipsychotic to a drug-free placebo pill for conditions that fell outside the drug's approved uses. They found another 231 studies that kept track of side effects linked to the drugs. Nearly all of the research was funded by drugmakers.
Taken together, the studies showed that atypical antipsychotics had no effect in patients with eating disorders or drug and alcohol abuse, and it wasn't clear if they helped people with personality disorders or post-traumatic stress disorder.
The drugs did have a small but consistent benefit for dementia patients with psychotic symptoms, however.
More people with an anxiety disorder taking Seroquel in particular got better compared with patients who took a placebo. And for those with obsessive-compulsive disorder, Risperdal worked better than a placebo. Still, those specific findings came from just three studies each.
But according to the findings, published in the Journal of the American Medical Association, the drugs also had side effects.
For instance, one in 10 elderly people treated with Zyprexa developed tremors and one in 53 on Risperdal suffered a stroke. Younger people on the drugs experienced weight gain, fatigue and other side effects.
Maher said that the decision to use one of these drugs for a non-approved condition should be based on a discussion between patients and their doctors, especially because some people may be more susceptible to side effects than others.
"Each individual patient needs to be considered as opposed to, 'This is good for this condition,'" she said.