Introduction - The aim of this study was to analyze the effectiveness of ga
bapentin administration to bipolar patients who had an incomplete response
to other mood stabilizers.
Subjects and methods - Twenty-two RDC bipolar 1 and II patients were assess
ed by means of the SADS and entered if they gave their consent to participa
te. Ail them had suffered from frequent relapses, subsyndromal features (mo
stly depressive) and incomplete response to other drugs. They all received
open-label increasing doses of gabapentin until clinical response. The pati
ents were assessed through the CGI-BP and a specific questionnaire at basel
ine and at 12 weeks of follow-up.
Results - Six out of the 22 patients dropped out for various reasons (four
because of relapse, one because of side effects and one more because of poo
r compliance). Eight of the 16 patients that completed the 12-week follow-u
p showed at least two stages of improvement in the CGI. Using the last obse
rvation-carried forward analysis, the improvement was statistically signifi
cant for the depression subscale, and apparently related to social function
ing, irritability and anxiety. Only one patient dropped out because of into
lerance (mild rash). The mean dose of gabapentin was 1,310 mg/day.
Conclusion - Gabapentin may be a useful drug for the add-on treatment of bi
polar patients with poor response to other mood stabilizers. Gabapentin may
improve depressive residual symptoms such as irritability, social withdraw
al or anxiety. These results should be confirmed in randomized clinical tri
als. (C) 2000 Editions scientifiques et medicales Elsevier SAS.