Lithium and Valproate Levels Do Not Correlate with Ketamine’s Antidepressant Efficacy in Treatment-Resistant Bipolar Depression

Figure 1

Rapid and sustained antidepressant effects of ketamine in treatment-resistant bipolar depressed patients maintained on therapeutic-dose lithium and valproate. Twenty-three subjects with treatment-resistant bipolar disorder (BD) receiving lithium (a) and 13 receiving valproate (b) currently experiencing a major depressive episode were randomized to either subanesthetic dose ketamine (0.5 mg/kg × 40 min) or placebo infusion in a randomized, placebo-controlled, crossover trial. Ketamine had antidepressant efficacy in both lithium-maintained and valproate-maintained patients (drug-by-mood stabilizer interaction (, )) but there was no statistically significant antidepressant difference between lithium and valproate (, , and ).

(a)

(b)