A retrospective evaluation of the impact of total smoking cessation on psychiatric inpatients taking clozapine.
OBJECTIVE
To investigate the effect of a complete smoking ban on a group of psychiatric inpatients maintained on the antipsychotic medication clozapine.


METHODS
Retrospective data on clozapine dose and plasma levels were collected from a three month period before and a six month period after the introduction of the smoking ban.


RESULTS
Before the ban only 4.2% of patients who smoked had a plasma clozapine level > or =1000 microg/l but after the ban this increased to 41.7% of the sample within the six month period following the ban despite dose reductions.


CONCLUSIONS
Abrupt cessation of smoking is associated with a potentially serious risk of toxicity in patients taking clozapine. Plasma clozapine levels must be monitored closely and adjustments made in dosage, if necessary, for at least six months after cessation.
Cormac
I
I
Nottinghamshire Healthcare NHS Trust, Rampton Hospital, Retford, Notts, UK. irene.cormac@nottshc.nhs.uk <irene.cormac@nottshc.nhs.uk>
Brown
A
A
Creasey
S
S
Ferriter
M
M
Huckstep
B
B
D014150:Antipsychotic Agents / Q000493:pharmacokinetics / Q000627:therapeutic use / Q000633:toxicity*; D003024:Clozapine / Q000493:pharmacokinetics / Q000627:therapeutic use / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004739:England; D005500:Follow-Up Studies; D006778:Hospitals, Psychiatric; D006801:Humans; D008657:Metabolic Clearance Rate / Q000187:drug effects; D009207:Myoclonus / Q000097:blood / Q000139:chemically induced; D011618:Psychotic Disorders / Q000097:blood / Q000188:drug therapy* / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D012640:Seizures / Q000097:blood / Q000139:chemically induced; D016540:Smoking Cessation / Q000706:statistics & numerical data*
D014150:Antipsychotic Agents; D003024:Clozapine