Acai berries, cumin, herbal teas, turmeric and long-term use of garlic, herbal supplements that are often considered beneficial to health, may have a negative impact on chemotherapy, according to a report presented at a recent meeting of the American Society of Clinical Oncology in Chicago. Researchers at Northwestern Memorial Hospital point to growing evidence that these popular supplements may exacerbate or diminish the effects of chemotherapy drugs and in some cases may lead to toxic, even fatal, reactions. Doctors urge cancer patients to discuss the use of supplements with their doctors before treatment begins. With the development of the Internet, patients have easier access to information about alternative products and often turn to dietary and herbal supplements to treat their condition. They believe they are natural and safe. However, June McKoy, a geriatrician at Northwestern Memorial Hospital and lead researcher on the report, noted that patients need to be aware that these supplements are more than just vitamins and that they can counteract the therapeutic effects if used inappropriately. He further noted that more research is needed to understand which supplements affect chemotherapy drugs and to what extent. Dr. McKoy recommends that patients should have an open discussion with their physicians about the use of vitamins and supplements. Herbal supplements are used for therapeutic purposes in plants or plant parts that can affect chemotherapy drugs through different mechanisms. Some herbs may interfere with the metabolism of chemotherapeutic drugs causing them to be less effective. And some herbs, such as garlic, can increase the risk of bleeding during surgery with prolonged use. While culinary herbs used for flavoring are usually safe when used in small doses, prolonged heavy use may have negative effects on the body after chemotherapy, and some recent surveys have shown that 50% of patients receiving chemotherapy do not tell their doctors that they are using alternative therapies. Dr. McKoy explained that a combination approach may actually benefit cancer patients, but the key is to use it for the right amount of time and to use it properly under the supervision of a physician. The report urges that patients should stop taking herbal supplements while receiving chemotherapy, and encourages that those interested in complementary therapies should discuss with their doctors therapeutic measures that may be beneficial to treatment. Integrative therapies such as massage, acupuncture and meditation can be helpful in addressing patient needs, such as reducing stress, relieving pain, and helping patients adapt. Dr. McKoy further emphasized the importance of physician and patient awareness of these potential interactions during treatment and encouraged that patients should inform their physicians of all their herbal supplement intake. It is also recommended that patients should carry the labels and bottles of the supplements they use to help their physicians adjust the dose and prevent toxicity from occurring. Dr. McKoy also plans to launch a pilot study this summer to investigate how often supplement use is discussed between cancer patients and their physicians, with an eye toward developing effective measures to improve patient-doctor communication to prevent potentially dangerous drug interactions.