Charms & Harms: St John's Wort (Hypericum perforatum)

Abstract

SUMMARY MESSAGE: St John’s wort is about as effective as some conventional antidepressants (NNT=42) including certain SSRIs for treating mild to moderate depression and has a favourable adverse effect profile, at least with short-term use. However, it interacts with several other medicines, including digoxin, theophylline, warfarin and oral contraceptives. As with all herbal medicines, different St John’s wort products differ in their pharmaceutical quality, and the implications of this for efficacy and safety should be considered.