Prophylactic effect of phenytoin in bipolar disorder: a controlled study.
OBJECTIVE
Phenytoin is an effective anticonvulsant that has not previously been studied prophylactically in bipolar (BP) patients. Thus a study of phenytoin prophylaxis was undertaken and is herein reported.


METHODS
Bipolar patients were studied who had at least one episode per year in the previous 2 years despite ongoing prophylaxis. Patients were stable for a mean of 4 months (range 1-13) before entering the study. Phenytoin or placebo was added to their current therapy in a double-blind cross-over design for 6 months in each phase. Thirty observation periods of 6 months each were studied for 23 patients.


RESULTS
Three patients had relapse on phenytoin and nine had relapse on placebo. There was a significant prophylactic effect of phenytoin in BP disorder [Cox's F-test for comparing survival in two groups: F(6, 18) = 3.44, p = 0.02].


CONCLUSIONS
This study suggests prophylactic effects of add-on phenytoin in BP illness. However, the number of patients was small and confirmation is necessary.
Mishory
A
A
Barzilai Hospital, Ashkelon Faculty of Health Sciences, Ministry of Health, Mental Health Center, Ben Gurion University of the Negev, Beersheva, Israel.
Winokur
M
M
Bersudsky
Y
Y
D000927:Anticonvulsants / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000188:drug therapy* / Q000517:prevention & control / Q000523:psychology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010672:Phenytoin / Q000009:adverse effects / Q000627:therapeutic use*; D055502:Secondary Prevention; D016896:Treatment Outcome
D000927:Anticonvulsants; D010672:Phenytoin