Common herbal supplement can cause dangerous interactions

June 30, 2014

St. John's wort, the leading complementary and alternative treatment for depression in the United States, can be dangerous when taken with many commonly prescribed drugs, according to a study by researchers at Wake Forest Baptist Medical Center.

The researchers reported that the can reduce the concentration of numerous drugs in the body, including oral contraceptive, blood thinners, cancer chemotherapy and blood pressure medications, resulting in impaired effectiveness and treatment failure.

"Patients may have a false sense of safety with so-called 'natural' treatments like St. John's wort," said Sarah Taylor, M.D., assistant professor of dermatology at Wake Forest Baptist and lead author of the study. "And it is crucial for physicians to know the dangers of 'natural' treatments and to communicate the risks to patients effectively."

The study is published in the current online issue of The Journal of Alternative and Complementary Medicine.

To determine how often S. John's wort (SJW) was being prescribed or taken with other medications, the team conducted a retrospective analysis of nationally representative data collected by the National Ambulatory Medical Care Survey from 1993 to 2010. The research team found the use of SJW in potentially harmful combinations in 28 percent of the cases reviewed.

Possible can include serotonin syndrome, a potentially fatal condition that causes high levels of the chemical serotonin to accumulate in your body, heart disease due to impaired efficacy of blood pressure medications or unplanned pregnancy due to contraceptive failure, Taylor said.

Limitations of the study are that only medications recorded by the physician were analyzed. However, she said the rate of SJW interactions may actually be underestimated because the database did not include patients who were using SJW but did not tell their doctor.

"Labeling requirements for helpful supplements such as St. John's wort need to provide appropriate cautions and risk information," Taylor said, adding that France has banned the use of St. John's wort products and several other countries, including Japan, the United Kingdom, and Canada, are in the process of including drug-herb interaction warnings on St. John's wort products.

"Doctors also need to be trained to always ask if the patient is taking any supplements, vitamins, minerals or herbs, especially before prescribing any of the common drugs that might interact with St. John's wort."

Co-authors are Steven Feldman, M.D., and Scott Davis, M.A., of Wake Forest Baptist. Funding was provided by the Center for Dermatology Research at Wake Forest Baptist.

Explore further: Steroids often prescribed for psoriasis, countering guidelines

Related Stories

Herbal remedies escape EU law

August 9, 2011

Many herbal remedies available over-the-counter in pharmacies and health food shops are still lacking important information needed for safe use, according to University of Leeds researchers.

Recommended for you

Researchers identify source of opioids' side effects

January 17, 2017

A commercially available drug may help drastically reduce two side effects of opioid painkillers—a growing tolerance and a paradoxical increased sensitivity to pain—without affecting the drugs' ability to reduce pain, ...

CVS generic competitor to EpiPen, sold at a 6th the price

January 12, 2017

CVS is now selling a rival, generic version of Mylan's EpiPen at about a sixth of its price, just months after the maker of the life-saving allergy treatment was eviscerated before Congress because of its soaring cost to ...

Many misuse OTC sleep aids: survey

December 29, 2016

(HealthDay)—People struggling with insomnia often turn to non-prescription sleep remedies that may be habit-forming and are only intended for short-term use, according to a new Consumer Reports survey.

The pill won't kill your sexual desire, researchers say

December 15, 2016

Taking the pill doesn't lower your sexual desire, contrary to popular belief, according to research published in the Journal of Sexual Medicine. The authors of the research, from the University of Kentucky and Indiana University ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.