Clozapine may cause side effects; most are minor, although some are serious and potentially fatal. Common side effects include extreme constipation, bed-wetting, night-time drooling, muscle stiffness, sedation, tremors, orthostatic hypotension, hyperglycemia, and weight gain. The risk of developing extrapyramidal symptoms such as tardive dyskinesia is below that of typical antipsychotics; this may be due to clozapine's anticholinergic effects. Extrapyramidal symptoms may subside somewhat after a person switches from another antipsychotic to clozapine.[20]
Clozapine also carries five black box warnings, including warnings for agranulocytosis, CNS depression, leukopenia, neutropenia, seizure disorder, bone marrow suppression, dementia, hypotension, myocarditis, orthostatic hypotension (with or without syncope) and seizures.