Clinical experience with gabapentin in patients with bipolar or schizoaffective disorder: results of an open-label study.
BACKGROUND
This study was carried out to evaluate the efficacy, tolerability, and safety of gabapentin as an adjunctive treatment in patients with bipolar or schizoaffective disorder with manic or hypomanic symptoms.


METHODS
Twenty-five patients fulfilling DSM-IV diagnostic criteria for bipolar I disorder or schizoaffective disorder underwent a 16-week, open-trial treatment with gabapentin. Symptom severity was measured using the Clinical Global Impressions scale (CGI) and the Brief Psychiatric Rating Scale (BPRS). Baseline scores and final scores were compared by using the Student t test and the Friedman range variance analysis.


RESULTS
Twenty-two patients (88%) completed the 16 weeks of treatment with gabapentin; 19 (76%) had a positive response as measured by changes in CGI and BPRS scores. The mean dose was 1440 mg/day. The only side effect observed was oversedation, which decreased with continuing treatment.


CONCLUSIONS
Gabapentin was effective in the treatment of mania and hypomania in patients with bipolar and schizoaffective disorders. If confirmed in controlled studies, these findings suggest that gabapentin represents a well-tolerated, rapidly acting antimanic agent.
Cabras
P L
PL
Department of Neurological and Psychiatric Sciences, University of Florence, Italy.
Hardoy
M J
MJ
Hardoy
M C
MC
Carta
M G
MG
D000085:Acetates / Q000009:adverse effects / Q000627:therapeutic use*; D000208:Acute Disease; D000328:Adult; D000368:Aged; D000588:Amines; D000927:Anticonvulsants / Q000009:adverse effects / Q000627:therapeutic use*; D018692:Antimanic Agents / Q000009:adverse effects / Q000627:therapeutic use; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001569:Benzodiazepines / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000188:drug therapy* / Q000523:psychology; D003509:Cyclohexanecarboxylic Acids; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D000077206:Gabapentin; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011618:Psychotic Disorders / Q000188:drug therapy* / Q000523:psychology; D016896:Treatment Outcome; D005680:gamma-Aminobutyric Acid
D000085:Acetates; D000588:Amines; D000927:Anticonvulsants; D018692:Antimanic Agents; D014150:Antipsychotic Agents; D003509:Cyclohexanecarboxylic Acids; D001569:Benzodiazepines; D005680:gamma-Aminobutyric Acid; D000077206:Gabapentin