What medications, herbs, and supplements can interact with St. John's Wort?

St. John's wort has been shown to interact with many prescription medications, but less so with other supplements. Integrative medicine specialist Tieraona Low Dog, MD, explains the guidelines to keep in mind about St. John's wort.

Transcript

00:00

There's a long, long list of medications that Saint John's wort interacts with. So I usually recommend it for people

00:06

who are not taking medications. [MUSIC PLAYING]

00:16

I remember in 1996 when Saint John's wort really just sort of came into the public awareness

00:23

as an herb that could be beneficial for people with depressed mood. And it was only a couple of years later that we began to hear all of these reports

00:31

about interactions with Saint John's wort and medications. Obviously, the most severe interactions

00:37

occurred in people who were taking medications to prevent them from rejecting one of their organs

00:44

that had been transplanted-- kidney, heart, et cetera. It was at that time we understood and started

00:51

looking-- researching-- into the interactions of Saint John's wort with different medications. We found out that actually, it can interact with up to 50%

01:01

of prescription medications. That's a big number. And some, like oral contraceptives,

01:07

you may not even be thinking about that there could be an interaction. In our movement now towards lower-estrogen birth control

01:15

pills, meaning we're using less estrogen, if you started taking Saint John's wort, studies have shown it can actually

01:22

increase breakthrough bleeding and possibly puts you at risk for pregnancy. So there's a long, long list of medications

01:30

that Saint John's wort interacts with. So I usually recommend it for people who are not taking medications.

01:36

If you are taking any medication and you choose to take Saint John's wort, please check with your health care

01:43

provider or your pharmacist. Pharmacists can also be a great resource because they have databases right there that

01:51

can pull up those risks of interactions right at the pharmacy level. Saint John's wort is a wonderful herb.

01:57

And other than its interactions with medications, it's extremely safe. Another question that I'm often asked

02:04

is, well, if it interacts with medications, will it interact with other herbs or other dietary supplements?

02:11

If there is an interaction with a vitamin or another herb, it's probably very, very minimal.

02:18

We're not seeing interactions of that kind. So I would say, if you're taking a multivitamin and you're taking Saint John's wort,

02:24

or you're taking glucosamine and you're taking Saint John's wort, these are not significant interactions you should be concerned about.

02:30

The main thing to be aware of is potential interactions with medications. [AUDIO LOGO]