CAM InteractionsSt. John's Wort

St. John’s wort and ibuprofen pharmacokinetics

“No ibuprofen [Advil, Motrin, Nuprin, Medipren] dose adjustments appear warranted when the drug is administered orally with St. John’s wort,” according to this study by Dr. Edward Bell in an article published in The Annals of Pharmacotherapy.

Here are the details.

  • 8 men participated in the study.
  • On day 1, each volunteer received one dose of ibuprofen 400 mg, and blood samples were drawn at regular intervals.
  • On days 2 to 22, the subjects took St. John’s wort 300 mg, 3 times each day.
  • The subjects then received a dose of ibuprofen 400 mg while continuing to take the St. John’s wort 3 times a day, and had blood drawn at regular intervals.

And the results.

  • There were no differences in peak blood levels of St. John’s wort.
  • No differences in the total amount of St. John’s wort absorbed by the body.

The bottom line?

It’s pretty easy to find cautionary statements on the Internet about taking St. John’s wort and ibuprofen at the same time. For example, MedlinePlus, eNotAlone, and Aetna InteliHealth all make the same statement, “St. John’s wort may increase anti-inflammatory effects of … NSAIDs like ibuprofen.”

In no case was this statement referenced.

I can find no studies where St. John’s wort interacted with ibuprofen. The association is based on individual patient reports.

4/16/07 20:39 JR, updated 1/8/10 22:16 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.