Ienjoyed reading the excellent review article on St John's wort by Gaster and Holroyd,1 with a balanced view on the pros and cons of its use for treatment of mental depression. As the authors indicated, the use of St John's wort has increased markedly worldwide in recent years, with annual sales of $200 million in the United States in 19972 and 111 million daily doses sold in Germany in the same year.3 This wide use is in contrast to the poor understanding of the pharmacokinetics, including drug interactions, of constituents of extract of St John's wort (Hypericum perforatum).
Cheng TO. St John's Wort Interaction With Digoxin. Arch Intern Med. 2000;160(16):2546. doi: