Potential treatment for subthreshold and mild depression: a comparison of St. John's wort extracts and fluoxetine

Subthreshold depressive disturbances and depressive episodes of mild severity are frequently associated with disability and socioeconomic burden, and often show an increase in symptomatology over time if untreated. Thus, there is an urgent need for antidepressant active compounds that are more readily available than those that must be obtained by prescription. To get an impression of the efficacy of the widely used phytopharmaceutical St. John's wort, the antidepressant efficacy in mild depressive disorders was compared with that of the standard antidepressant fluoxetine. The present overview includes controlled trials of fluoxetine in depression with a mean initial score on the Hamilton Rating Scale for Depression (HAM-D) < or =24, which were compared to the respective studies on St. John's wort. The mean HAM-D reduction of all St. John's wort studies was 10.2 (52.9%), and the respective figures for fluoxetine were 12.5 points and 55.5%. Thus, no relevant efficacy difference between the groups of investigations was found based on the studies included. The most important restrictions of this overview are no meta-analysis was performed, the studies were performed with heterogeneous methodological standards, and the St. John's wort extracts used were very different. However, St. John's wort might be a treatment option to reduce symptoms in patients not suffering from full-blown depressive disorder.