clozapine; Clozaril, Fazacio ODT (cont.)

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.

The most common side effect of clozapine is drowsiness.

Other important side effects include:

Clozapine has anticholinergic effects that interfere with the function of smooth muscles. This can lead to blurred vision and difficulty urinating (when there is enlargement of the prostate) due to effects on the muscles of the eye and bladder. Clozapine slows the intestine and leads to constipation in approximately 14% of patients. Paralysis of the intestinal muscles can lead to paralytic ileus, a condition in which the intestine stops working.

Medically Reviewed by a Doctor on 1/27/2015


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