St. John’s wort and dangerous drug interaction

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St. John’s wort is the leading alternative treatment for depression in the United States. What many people don’t know is that combining St. John’s wort with many commonly prescribed drugs can be dangerous.

Alters a variety of medications

Researchers from Wake Forest Baptist Medical Center reported that the herbal supplement can reduce the concentration of numerous drugs in the body. This includes birth control/oral contraceptive, blood thinners, cancer chemotherapy and blood pressure medications. Impaired effectiveness and treatment failure may ensure. “Patients may have a false sense of safety with so-called ‘natural’ treatments like St. John’s wort,” explained Sarah Taylor, MD, assistant professor of dermatology at Wake Forest Baptist and lead author. “And it is crucial for physicians to know the dangers of ‘natural’ treatments and to communicate the risks to patients effectively.”

Almost a third in survey exposed to potentially harmful drug combinations

The research team conducted an analysis of nationally representative data collected by the National Ambulatory Medical Care Survey from 1993 to 2010. They found St. John’s wort in potentially harmful drug combination in 28% of the cases reviewed. The percentage may be higher since not all doctors asked about St. John’s wort use. Drug interactions include serotonin syndrome, a potentially fatal condition causing high levels of serotonin to accumulate in the body, heart disease due to impaired efficacy of medications, and unwanted pregnancy due to contraceptive failure.

Labelling requirements, doctor dialogue strongly recommended

“Labeling requirements for helpful supplements such as St. John’s wort need to provide appropriate cautions and risk information,” Taylor noted. She also revealed that France has banned the use of St. John’s wort and other countries like Japan, the UK, and Canada are in the process of adding drug-herb interaction warnings on the 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.”

Source: MedicalNewsToday, The Journal of Alternative and Complementary Medicine

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