Open-label pilot study of memantine in the treatment of compulsive buying

BACKGROUND: Although compulsive buying (CB) is relatively common, pharmacotherapy research for CB is limited. Memantine, an N-methyl-D-aspartate receptor antagonist, appears to reduce glutamate excitability and improve impulsive behaviors, suggesting it may help individuals with CB. METHODS: Nine patients (8 females) with CB were enrolled in a 10-week open-label treatment study of memantine (dose ranging from 10 to 30 mg/d). Participants were enrolled from December 2008 until May 2010. The primary outcome measure was change from baseline to study end-point on the Yale-Brown Obsessive Compulsive Scale-Shopping Version (Y-BOCS-SV). RESULTS: Of the 9 participants, 8 (88.9%) completed the 10-week study. Y-BOCS-SV scores decreased from a mean of 22.0 ± 1.3 at baseline to 11.0 ± 5.3 at endpoint (P < .001). Hours spent shopping per week and money spent shopping both decreased significantly (P < .001). The mean effective dose of memantine was 23.4 ± 8.1 mg/d. Memantine treatment was associated with diminished impulsive buying and improvements on cognitive tasks of impulsivity. In addition, the medication was well-tolerated. CONCLUSIONS: These findings suggest that pharmacologic manipulation of the glutamate system may target the impulsive behavior underlying CB. Placebo-controlled, double-blind studies are warranted in order to confirm these preliminary findings in a controlled design.