Researchers from the Mayo Clinic in Rochester, Minnesota have reviewed the evidence and report that most interactions are confined to a relatively small number of drug classes and supplements.

First, the details.

  • 1818 patients treated at the Mayo Clinic in 6 different specialty clinics were surveyed for their use of dietary supplements.
  • Concurrent use of prescription drugs was obtained from patients’ medical records.
  • A computerized search was used to assess the potential significance of each interaction on the patients’ health.

And, the results.

  • 710 (40%) of the 1795 patients who responded reported use of dietary supplements.
  • 107 interactions with potential clinical significance were identified.
  • The 5 most common natural products with a potential for interaction accounted for 68% of the potential clinically significant interactions.
    • Garlic
    • Valerian
    • Kava
    • Ginkgo
    • St John’s wort
  • The 4 most common classes of prescription medications with a potential for interaction accounted for 94% of the potential clinically significant interactions.
    • Antithrombotic medications
    • Sedative
    • Antidepressant drugs
    • Antidiabetes drugs

The bottom line?
No patient was harmed seriously from any interaction.

It’s still a good idea to include a list of your supplements with your prescription drugs when you go to the doctor.

3/22/08 20:31 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.