A retrospective study of the safety of intramuscular ziprasidone in agitated elderly patients.
OBJECTIVE
Authors evaluated the safety of intramuscular ziprasidone for use in acute agitation in an elderly population.


METHODS
Medical records were reviewed retrospectively to identify consecutive patients who were admitted to our neuropsychiatry service with the presenting complaint of dementia (DSM-IV) with agitation and who were given intramuscular ziprasidone and then administered an electrocardiogram (ECG) (N = 23). Some patients also had a baseline ECG (N = 14). QTc intervals were recorded, and significance was defined as a QTc of > or =450 ms or a 10% prolongation from baseline. A paired-samples t test was performed to compare the baseline and postmedication QTc intervals. Confounding factors were examined, and cardiac events (torsades de pointes, cardiac arrest) were recorded.


RESULTS
There was no significant difference in the QTc interval between the baseline and the post-ziprasidone values. One patient had a QTc greater than 500 ms and 25% over baseline, and therefore the medication was discontinued. The mean prolongation of the QTc interval was only 0.5 ms. There were no episodes of torsades de pointes. Other medications that the patients were taking did not appear to affect the QTc interval in an expected manner.


CONCLUSIONS
Larger studies need to be done to evaluate the safety of intramuscular ziprasidone in agitated elderly patients, a population with an increased risk of QT prolongation and torsades de pointes because of their age, comorbid conditions, and concomitant use of multiple medications.
Greco
K Elizabeth
KE
Emory University School of Medicine, Atlanta, Ga. 30329, USA
Tune
Larry E
LE
Brown
Frank W
FW
Van Horn
William A
WA
D000368:Aged; D000369:Aged, 80 and over; D014150:Antipsychotic Agents / Q000008:administration & dosage* / Q000009:adverse effects* / Q000494:pharmacology; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000453:epidemiology; D003704:Dementia / Q000188:drug therapy / Q000523:psychology*; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006220:Haloperidol / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D007273:Injections, Intramuscular; D008133:Long QT Syndrome / Q000139:chemically induced / Q000175:diagnosis / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000008:administration & dosage* / Q000009:adverse effects* / Q000494:pharmacology; D011595:Psychomotor Agitation / Q000188:drug therapy*; D012189:Retrospective Studies; D012307:Risk Factors; D013844:Thiazoles / Q000008:administration & dosage* / Q000009:adverse effects* / Q000494:pharmacology; D016171:Torsades de Pointes / Q000139:chemically induced / Q000175:diagnosis / Q000453:epidemiology
D014150:Antipsychotic Agents; D010879:Piperazines; D013844:Thiazoles; C092292:ziprasidone; D006220:Haloperidol