Home HealthTopics Health Centers Reference Library Research
Join us on Facebook Join us on Facebook Share on Facebook


Herbal, Dietary Supplements Can Affect Cancer Treatments

The use of vitamin and herbal supplements and other complementary and alternative therapies continues to grow in popularity. Studies by the Centers for Disease Control and Prevention have shown that up to 64 percent of patients acknowledge practicing some form of complementary or alternative therapy, including meditation, dietary changes, and exercise, in an effort to improve their quality of life.

However, cancer patients should be cautious of drug interactions when taking dietary or herbal supplements along with chemotherapy, radiation or conventional cancer treatments. Many cancer patients do not tell their doctors when they are using these agents to help alleviate pain, fatigue, or depression.

About 30 percent of patients will use natural products because they think they’re safe, but these herbal and dietary supplements can cause unwanted drug interactions and serious side effects. For example, St. John's Wort interacts with oral contraceptives and hypertension medication.

Additionally, patients who ingest the herb to help with depression or anxiety may not realize that it can adversely interact with their chemotherapy treatment. St. John’s Wort can speed up or slow down the metabolism of the chemotherapy drug, changing its effect. If the drug is metabolized too quickly and leaves the body too soon, it won’t be effective. If the drug is metabolized too slowly and remains in the body too long, it can become toxic.

Cancer patients often take the herb Ginkgo biloba to help improve short-term memory loss associated with chemotherapy, not realizing that it can cause spontaneous bleeding and seizures. Gingko biloba, along with garlic and ginger, can increase the risk of bleeding because it is a natural blood-thinner. This can cause problems for cancer patients who are taking chemotherapy drugs that may also thin their blood.

The important thing is for patients to talk to their health care providers about taking these natural products. Open communication is the key to healthy treatment.

This article is based on information provided by The Ohio State University Medical Center Media Relations Office and was adapted for use on NetWellness with permission, 2008.

For more information:

Go to the Cancer health topic, where you can:

Last Reviewed: Dec 15, 2008

Bella   Mehta, PharmD, BS Bella Mehta, PharmD, BS
Associate Professor of Clinical Pharmacy
College of Pharmacy
The Ohio State University