Medicinal Plants: A Complementary and Alternative Antidepressant Therapy

There is enough data available now to believe that nature has provided cure of almost every ailment through herbal medicine or management. Therefore, now there is lot of emphasis on identification, evaluation, development and characterization of numerous plants and their active constituents against several diseases including depression. Depression is not only one of the most common ailments but also a highly complex condition to study. Even though several antidepressant drugs are available now, yet their effectiveness and usefulness are highly questionable especially because of their side effects. As herbal remedies are generally associated with favourable safety profiles therefore they have the possible potential to deliver effective replacements to currently available synthetic antidepressants. More recently, efforts have been focused on characterization of pharmacologically active ingredients and to identify the mode of action of herbal antidepressant medicines. This review describes a brief introduction of different animal models for depression and discusses the advantages and disadvantages for each approach. Then we have summarized possible plant phytochemicals as antidepressant drug and their underlying mechanisms. In the main body of the review, we have discussed in detail the most frequently used plants (21) being investigated for the treatment of depression. Additionally, we have provided the list of medicinal plants (92) representing their origin, parts used, extraction method, evaluation method and possible active ingredient. In the final part of the review we have presented the summary of clinical trials on the use of medical plants for depression and their active constituents.