- Background: Inositol has been reported to be an effective treatment in depression, and we hypothesized that inositol addition might enhance or speed up response to serotonin selective reuptake inhibitors (SSRI). Methods: Twenty-seven depressed patients completed a double-blind controlled 4-week trial of SSRI plus placebo or SSRI plus inositol. Hamilton Depression Rating Scale was used as an assessment tool at baseline, and 1, 2, 3, and 4 weeks. Results: No significant difference was found between the two treatment groups. Conclusions: Previous studies combining different effective antidepressant therapies similarly found no evidence for additive effects [e.g., monoamine oxidase inhibitors (MAOI) plus tricyclic antidepressants (TCA), TCA plus lithium]. By contrast, augmentation by lithium or MAOI after a failed course of antidepressant treatment is effective and should be studied with inositol.