Review of Herbal Medicines for the Treatment of Depression

Abstract

Depression, a mental illness that is receiving increasing attention, is caused by multiple factors and genes and adversely affects social life and health. Several hypotheses have been proposed to clarify the pathogenesis of depression, and various synthetic antidepressants have been introduced to treat patients with depression. However, these drugs are effective only in a proportion of patients and fail to achieve complete remission. Recently, herbal medicines have received much attention as alternative treatments for depression because of their fewer side effects and lower costs. In this review, we have mainly focused on the herbal medicines that have been proven in clinical studies (especially randomized controlled trials and preclinical studies) to have antidepressant effects; we also describe the potential mechanisms of the antidepressant effects of those herbal medicines; the cellular and animal model of depression; and the development of novel drug delivery systems for herbal antidepressants. Finally, we objectively elaborate on the challenges of using herbal medicines as antidepressants and describe the benefits, adverse effects, and toxicity of these medicines.