title: Clozapine withdrawal symptoms in a Parkinson's disease patient.
abstract: Abrupt clozapine withdrawal can cause rebound psychosis and severe somatic symptoms in psychiatric patients. We report on the case of an advanced Parkinson's disease patient who developed myoclonus, tremor, rigidity, hyperreflexia, and stupor after abrupt clozapine withdrawal. The patient's symptoms resolved with treatment with cyproheptadine. This clinical picture suggests serotonergic rebound as an explanation for the patient's symptoms, although other pharmacological mechanisms are possible. Clozapine should be gradually withdrawn over a period of 1 to 2 weeks when possible, and abruptly discontinued only when necessary.
authors.affiliation: Department of Neurology, Parkinson's Disease and Movement Disorders Center, University of South Florida and Tampa General Healthcare, Tampa, Florida 33606, USA. tzesiewi@hsc.usf.edu
authors.forename: Theresa A
authors.initials: TA
authors.lastname: Zesiewicz
authors.forename: Sujatha
authors.initials: S
authors.lastname: Borra
authors.forename: Robert A
authors.initials: RA
authors.lastname: Hauser
mesh_terms: D000368:Aged; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D002230:Carbidopa / Q000009:adverse effects* / Q000627:therapeutic use; D003024:Clozapine / Q000009:adverse effects* / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D006212:Hallucinations / Q000139:chemically induced* / Q000188:drug therapy; D006801:Humans; D007980:Levodopa / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D009460:Neurologic Examination; D010300:Parkinson Disease / Q000188:drug therapy*; D010302:Parkinson Disease, Secondary / Q000139:chemically induced* / Q000175:diagnosis; D013375:Substance Withdrawal Syndrome / Q000175:diagnosis*
chemical_list: D014150:Antipsychotic Agents; D004338:Drug Combinations; C009265:carbidopa, levodopa drug combination; D007980:Levodopa; D003024:Clozapine; D002230:Carbidopa