Clozapine Best for Reducing Violence in Patients With Schizophrenia and Conduct Disorder

Clozapine was 4 times more likely than haloperidol to reduce violence in patients with schizophrenia and conduct disorder, a study published in The American Journal of Psychiatry found. 

“This study is the first to examine the effect of clozapine in violent schizophrenia patients with conduct disorder,” researchers wrote. “When conduct disorder is present, clozapine is the optimal treatment.”

The 12-week, double-blind study was a head-to-head comparison of clozapine, olanzapine, and haloperidol in 99 patients hospitalized with schizophrenia who were physically assaultive.

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Researchers categorized patients based on the presence or absence of conduct disorder before age 15 and found that, during the study, those with a history of conduct disorder had more frequent and severe assaults than those without conduct disorder.

Clozapine outperformed both olanzapine and haloperidol in reducing assaults in participants, according to the study. Olanzapine, meanwhile, outperformed haloperidol.

Compared with patients without conduct disorder, clozapine’s anti-aggressive superiority over haloperidol was significantly more pronounced in patients with conduct disorder.

“In patients with conduct disorder, clozapine was 4 times more likely than haloperidol to result in lower violence; in patients without conduct disorder, it was 3 times more likely to do so,” researchers reported.

Olanzapine, too, had a more pronounced superiority over haloperidol when conduct disorder was present. 

—Jolynn Tumolo

Reference

Krakowski M, Tural U, Czobor P. The importance of conduct disorder in the treatment of violence in schizophrenia: efficacy of clozapine compared with olanzapine and haloperidol. The American Journal of Psychiatry. 2021 January 21;[Epub ahead of print].