Here's what Hyla Cass, M.D., author of St. John's Wort : Nature's Blues Buster had to say about mixing St. John's Wort with prescription antidepressants:
- I have used St. John's wort with patients who were already on antidepressants, including Prozac, Zoloft, Effexor (venlafaxine hydrochloride), and the tricyclics (see Prozac and Beyond-The Synthetic Antidepressants), as well as those taking the amino acids such as tyrosine. Of possible concern in these cases is "serotonin syndrome," or an excessive serotonin buildup in the brain. There is no record of this occurring, despite thousands of people having taken the combination of St. John's wort and SSRIs. When asked about this possibility, Dr. Jerry Cott, a psycho- pharmacologist at the National Institute of Mental Health, asserted that "there have been no deaths or toxic reactions, no adverse interactions related to MAO inhibition, and no incidents of serotonin syndrome reported in the literature. There is no clear evidence that serotonin is even [activated] by St. John's wort in . . . animal studies or in human trials." It is clear that more research is needed before we fully understand how this herb works.
As further anecdotal evidence of no adverse reaction, I personally have taken St. John's Wort as soon as the day following my last dose of Prozac, an SSRI, with no adverse effects whatsoever. As always, however, it is wise to be under a doctor's supervision if you are mixing herbs with your regular medications or are planning to switch from a prescription medication to St. John's Wort. If you desire further information about using St. John's Wort to fight depression, Dr. Cass' book St. John's Wort : Nature's Blues Buster is an excellent reference for you and your physician.