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My son is in the prodromal phase of schizophrenia. Several psychiatrists have suggested that Clozaril is the best drug to treat schizophrenia even though there is a 1% to 2% chance of agranulocytosis, and thus drawing blood to check for this potential problem is neccessary.

I've done quite a bit of research and it does seem that Clozaril can be more effective. Why is this drug not used more in the U.S.?

Answered by: Cheryl Corcoran

With all due respect, I do not understand how it has been established that your son is in the prodromal phase of schizophrenia.

If he has symptoms consistent with a heightened risk for schizophrenia - social withdrawal, psychotic-like symptoms - then his risk for schizophrenia is still only about a third or less. We do not know yet what would be a safe and effective intervention for young people who seem to be at risk. Antipsychotics are likely not the proper treatment for this risk state, as in clinical trials, they have been associated with significant side effects, including dramatic weight gain. Further, no one has evaluated Clozaril as a treatment for the psychosis risk state.

As for Clozaril, it is a very effective medication for schizophrenia (though not for its prodrome). It treats psychosis in a number of patients whose symptoms have not responded to any other medications. And it may help reduce suicidal and violent thoughts and behavior in individuals with schizophrenia.

Clozaril should be used much more than it is in the US. To be used safely though, patients must have weekly blood draws to make sure the Clozaril is not suppressing their bone marrow and the production of white blood cells, necessary to fight infection. They must also be monitored closely for a whole host of potential problems, including hyperglycemia (high blood sugar), seizure risk, sedation, and effects on the heart and gastrointestinal system.

Clozaril is a very effective medication that also can have very serious side effects. It is probably not used more in the United States because 1) doctors are nervous about the potential side effects, and 2) systems of care are not routinely set up to support all the monitoring that is needed when someone takes Clozaril.

In the past, I directed a Clozaril Clinic at Yale, which treated a few hundred individuals with schizophrenia, mostly successfully, though we had to manage side effects in many individuals. Such programs I believe should be implemented more widely in psychiatric clinics.