clozapine; Clozaril, Fazacio ODT (cont.)

DRUG INTERACTIONS: Risperidone (Risperdal) may cause an increase in the amount of clozapine in the blood. This could lead to an increased risk of side effects from clozapine.

PREGNANCY: There are no adequate studies of clozapine in pregnant women. Studies in animals suggest no important effects on the fetus. Clozapine can be used in pregnancy if the physician feels that it is necessary.

NURSING MOTHERS: Animal studies suggest that clozapine is secreted in breast milk. Therefore, women taking clozapine should not nurse their infants.

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.

Among elderly patients with dementia-related psychosis, treatment with clozapine is associated with an increased risk of death for unclear reasons. Clozapine is not approved for use in dementia-related psychosis.

Seizures have occurred in approximately 1 of every 20 to 30 persons receiving clozapine. Patients receiving higher doses seem to be at higher risk.

Dizziness may occur in 1 of 5 persons taking clozapine. In some cases this may be due to orthostatic hypotension, a marked decrease in blood pressure that occurs when going from a lying or sitting position to a standing position. The drop in blood pressure may lead to loss of consciousness or even cardiac and respiratory arrest. This reaction is more common during the first few weeks of therapy while the dose is increasing, when drug is stopped briefly, or when patients are taking benzodiazepines such as diazepam (Valium) or other anti-psychotic drugs.



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