Impulsivity in patients with bipolar disorder and cocaine or amphetamine dependence given lamotrigine

Objective: Impulsivity is a component of bipolar disorder, substance-related disorders, and antisocial personality disorder. Method: Barratt Impulsiveness Scale nonplanning subscale (BIS-11- NP) scores were assessed from 2001-2003 in 37 outpatients in Dallas, Texas with bipolar disorder and cocaine or amphetamine dependence during therapy with lamotrigine. Results: Baseline BIS-11-NP scores correlated positively with baseline suicidality. BIS-11-NP scores decreased significantly from baseline to exit. Baseline to exit change on the BIS-11-NP correlated with change in some psychiatric symptom measures, drug craving, and days of drug use. A limitation of the study is the small sample size. Conclusion: The results suggest that lamotrigine is associated with decreased impulsivity.