title: Association of Clozapine with Seizures: A Brief Report Involving 222 Patients Prescribed Clozapine.
abstract: OBJECTIVE
  To study the prevalence and incidence of seizures in patients prescribed clozapine.
  
  
  METHODS
  The treatment records of 222 patients commenced on clozapine were retrospectively reviewed during the period of January 2007 to June 2014 to evaluate the prevalence of seizures before and after starting clozapine.
  
  
  RESULTS
  The majority of patients commenced on clozapine were male (65%), single (65%), and unemployed (57%). The mean (± standard deviation) dose of clozapine was 277.9 ± 102.5 mg/day. A history of seizure was present in 6 patients who were also prescribed antiepileptic medication; of these 6 patients, only 1 case had recurrence of seizure while taking clozapine due to poor compliance with ongoing antiepileptic medication. The incidence rate of new-onset seizure with clozapine was 6% (12/216). Most patients who developed seizures were male, aged between 24 and 41 years, and had a long duration of illness (≥ 10 years). The risk of seizure was associated with the dose of clozapine used: 3% (5/159) with dose up to 300 mg/day, 8% (4/49) with 325 to 500 mg/day, and 38% (3/8) in those receiving > 500 mg/day. More than half of the patients (7/12) who developed seizures while prescribed clozapine were managed with reduction in the dose of clozapine. In one-third of cases (4/12) an antiepileptic medication was added and in 1 case, clozapine was stopped. All patients who continued on clozapine remained seizure-free at follow-up that ranged from 6 months to 4 years.
  
  
  CONCLUSIONS
  The incidence of seizures with clozapine was 6% and the risk of seizures increased with higher doses.
authors.affiliation: Department of Psychiatry, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: S
authors.initials: S
authors.lastname: Grover
authors.affiliation: Department of Psychiatry, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: N
authors.initials: N
authors.lastname: Hazari
authors.affiliation: Department of Psychiatry, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: S
authors.initials: S
authors.lastname: Chakrabarti
authors.affiliation: Department of Psychiatry, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: A
authors.initials: A
authors.lastname: Avasthi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000927:Anticonvulsants / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D003024:Clozapine / Q000009:adverse effects* / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D012559:Schizophrenia / Q000188:drug therapy; D012640:Seizures / Q000139:chemically induced* / Q000517:prevention & control; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D014150:Antipsychotic Agents; D003024:Clozapine
keywords: Clozapine; Drug-related side effects and adverse reactions; Seizures