June 2013

Concurrent Use of Antidepressants and St. John's Wort Studied

Many people may be taking St. John's wort in addition to antidepressants, which may pose a dangerous risk of interaction, according to a study.

Extracts of Hypericum perforatum L. (St. John's wort) have been recommended traditionally for a wide range of medical conditions. The most common modern-day use of St. John's wort is the treatment of depression. Numerous studies report St. John's wort to be more effective than placebo and equally effective as tricyclic antidepressant drugs in the short-term treatment of mild-to-moderate major depression (1-3 months). It is not clear if St. John's wort is as effective as selective serotonin reuptake inhibitor (SSRI) antidepressants such as sertraline (Zoloft®). Recently, controversy has been raised by two trials of St. John's wort for major depression that did not show any benefits. However, due to problems with the designs of these studies, further research is warranted. Overall, the scientific evidence supports the effectiveness of St. John's wort in mild-to-moderate major depression. The evidence in severe major depression remains unclear.

St. John's wort may cause many serious interactions with prescription drugs, herbs, or supplements. Therefore, people using any medications should consult their healthcare providers including their pharmacist prior to starting therapy.

In the current study, researchers examined the use of St. John's wort with selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), which may be a potentially dangerous combination. They reviewed data from 266,848 people who had participated in the 45 and Up study. The participants reported receiving treatment for conditions such as depression or anxiety in the last four weeks.

Almost six percent of study participants received depression or anxiety treatment. Of these, almost five percent took an SSRI while 1.3 percent took an SNRI. About 0.3 percent of these individuals also took St. John's wort. The use of SSRIs and SNRIs were more common among women, as was the use of St. John's wort. The use of antidepressants decreased after 65 years of age. A total of 141 people reported using an SSRI and an SNRI at the same time, while 11 people said that they used an SSRI with St. John's wort.

The researchers concluded that it is of concern that there is some concurrent use of SSRIs with St. John's wort. Further study is needed in this area.

There is strong scientific evidence supporting the use of St. John's wort for depression. Light therapy and music therapy are also backed by strong evidence for this purpose.

For more information about St. John's wort, please visit Natural Standard's Foods, Herbs & Supplements Database.


  1. Natural Standard: The Authority on Integrative Medicine. 
  2. Rahman SZ, Basilakis J, Rahmadi A, et al. Use of serotonergic antidepressants and St John's wort in older Australians: a population-based cohort study. Australas Psychiatry. 2013 Jun;21(3):262-6. doi: 10.1177/1039856213475681. Epub 2013 Feb 25.

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