16-week Comparative Effectiveness Trial of Lamotrigine vs. Fluoxetine for Bipolar Depression

Lamotrigine dosing: 25 mg daily x 2 weeks, 50 mg daily x 2 weeks, 100 mg daily x 2 weeks, 200 mg (100 mg bid)) x 4 weeks. If patient still has at least mild depressive symptoms, the dose can be increased to 300 mg daily for 2 weeks and 400 mg for 4 weeks. Dose will be held for treatment response and can be reduced for side effects.

Fluoxetine dosing: 20mg for month 1, 40mg for month 2, and if still depressed (CGI ≥ 3) 60mg for month 3 and 4. Lower doses of fluoxetine will be prescribed for those with side effects. For known Cytochrome P450 2D6 poor metabolizers, fluoxetine will not be dosed \> 40mg.