Prospective observational multi-poison center study of ziprasidone exposures.
BACKGROUND
Ziprasidone is an atypical antipsychotic associated with QTc prolongation during therapeutic use. We characterized the clinical manifestations associated with ziprasidone overdoses, in particular the incidence and severity of QTc prolongation.


METHODS
Four regional poison centers prospectively collected ziprasidone overdose data from August 1, 2003 to October 1, 2005. Cases were included if they were followed to known medical outcome and comprised single-substance ziprasidone exposures or with co-ingestants not associated with prolongation of the QTc interval.


RESULTS
Fifty-six ziprasidone exposures met inclusion criteria. The most common clinical effects were drowsiness (N=38, 67.9%) and tachycardia (N=19, 33.9%). QTc prolongation (>0.500 second) occurred in only one patient. Seven patients had QTc intervals of 0.450 to 0.500 second. Medical outcomes were coded as no effect (13, 23.2%), minor effect (21, 35.5%), moderate effect (20, 35.7%), or major effect (2, 3.4%).


CONCLUSIONS
Common clinical effects following ziprasidone overdose are drowsiness and tachycardia. Clinically significant QTc prolongation occurs infrequently.
Klein-Schwartz
Wendy
W
Maryland Poison Center, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, USA. wkleinsc@rx.umaryland.edu
Lofton
Amanda L
AL
Benson
Blaine E
BE
Spiller
Henry A
HA
Crouch
Barbara I
BI
D000293:Adolescent; D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000506:poisoning*; D062787:Drug Overdose; D005260:Female; D006801:Humans; D008133:Long QT Syndrome / Q000139:chemically induced / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000506:poisoning*; D011039:Poison Control Centers; D011446:Prospective Studies; D012894:Sleep Stages; D013610:Tachycardia / Q000139:chemically induced / Q000503:physiopathology; D013844:Thiazoles / Q000506:poisoning*
D014150:Antipsychotic Agents; D010879:Piperazines; D013844:Thiazoles; C092292:ziprasidone