People who take antipsychotic drugs to treat psychiatric illnesses are less likely to commit a violent crime compared to when they are not on such medication.

According to a new study published in The Lancet, patients who take mood stabilizing medication are also much less likely to engage in violent crime, although this is true only for those who suffer from bipolar disorder.

Led by Dr. Seena Fazel of Oxford University, UK, the study looked at Swedish national health registries to analyze the psychiatric diagnoses, as well as any criminal convictions that may have followed, of more than 80,000 patients between the years 2006 and 2009 who were on antipsychotic or mood stabilizing drugs.

Over this three-year period, the researchers discovered that violent crime dropped by 45 percent in those patients who took antipsychotic drugs, and 24 percent in those who were on mood stabilizers.

Until now, there has been very little data and evidence of the effects of these drugs on adverse outcomes in the real world, including violent behavior. The findings in this new study not only suggests that patients on these medications are less likely to participate in violent crime, but also less likely to relapse and be re-hospitalized for their psychiatric illness.

“Patients with psychiatric disorders are at risk of perpetrating violent acts, as well as being victims. Until now, we have not known whether antipsychotics and mood stabilizers reduce risks of violence. By comparing the same people when they are on medication compared to when they are not, our study provides evidence of potentially substantial reductions in risk of violence, and suggests that violence is to a large extent preventable in patients with psychiatric disorders,” said Dr. Fazel in a statement.