clozapine; Clozaril, Fazacio ODT
GENERIC NAME: clozapine
BRAND NAME: Clozaril, FazaClo, Versacloz
DRUG CLASS AND MECHANISM: Clozapine is an anti-psychotic medication that works by blocking receptors in the brain for several neurotransmitters (chemicals that nerves use to communicate with each other) including dopamine type 4 receptors, serotonin type 2 receptors, norepinephrine receptors, acetylcholine receptors, and histamine receptors. Unlike traditional anti-psychotic agents, such as chlorpromazine (Thorazine) and haloperidol (Haldol) as well as the newer anti-psychotics, risperidone (Risperdal) and olanzapine (Zyprexa), clozapine only weakly blocks dopamine type 2 receptors.
PRESCRIBED FOR: Clozapine is use in the management of psychotic disorders including schizophrenia. Because of concern for the side effect of agranulocytosis (see side effects), clozapine should be reserved for patients who have failed to respond to other standard medications or who are at risk for recurring suicidal behavior.
SIDE EFFECTS: Clozapine may cause a severe reduction in white blood cell count, a condition known as agranulocytosis, in approximately 1 in 100 patients who take it for at least one year. White blood cells fight infections, and a severe reduction in white blood cells can result in severe infections. If not caught early, agranulocytosis can be fatal. Therefore, the white blood cell count should be measured (with a blood test) prior to starting treatment and regularly (weekly) while patients receive this medication, and for 4 weeks after it is stopped.
Medically Reviewed by a Doctor on 1/27/2015
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