Efficacy of vitamin C as an adjunct to fluoxetine therapy in pediatric major depressive disorder: a randomized, double-blind, placebo-controlled pilot study

Background: Current antidepressants used to treat pediatric patients have the disadvantage of limited efficacy and potentially serious side effects. The purpose of this study was to assess the efficacy of vitamin C as an adjuvant agent in the treatment of pediatric major depressive disorder in a six-month, double-blind, placebo-controlled pilot trial. Methods: The study group (n= 12) was given fluoxetine (10-20 mg/day) plus vitamin C (1000 mg/day) and control group (n= 12) administered fluoxetine (10-20 mg/day) plus placebo. The data were analyzed by ANOVA and t-test for independent samples. Results: Both groups demonstrated significantly improved scores on the Children's Depression Rating Scale (CDRS), the Children's Depression Inventory (CDI), and the Clinical Global Impression (CGI). ANOVA was significantly different on all clinical measurements (group effect, time effect, and interaction), with the exception of group effect and interaction for CGI. Patients treated for six months with fluoxetine and vitamin C showed a significant decrease in depressive symptoms in comparison to the fluoxetine plus placebo group as measured by the CDRS (t= 11.36, P< 0.0001) and CDI (t= 12.27, P< 0.0001), but not CGI (t= 0.13, P= 0.90). No serious adverse effects were observed. Conclusions: These preliminary results suggest that vitamin C may be an effective adjuvant agent in the treatment of MDD in pediatric patients.