February 6, 2009

Elderly At Risk From Some Herbal Medications

Older people, who are more likely to take prescription medications and suffer from chronic diseases, face increased risks when taking herbal or dietary supplements, said an expert at Baylor College of Medicine and colleagues in a report that appears in the Annals of Long Term Care.

"Older people tend to take multiple medications," said Dr. Donald M. Marcus, professor emeritus of medicine-immunology, allergy and rheumatology at BCM.  "This could make them more vulnerable to drug interactions and the toxicities of herbal medicines."

"Many herbal medications have the same chemicals as prescription medications, but with the prescription medications that contain a purified form of those chemicals, we have a better idea of what the active ingredients are, what the benefits are and what the side effects might be," he said.

"Many people think that herbal medications are safer because they are natural, but the body does not distinguish whether something came from nature or a test tube.  Drugs are also discovered in nature.  Just like any other drug, these medications have reactions and interactions with the body," said Dr. Holly Holmes, assistant professor of general internal medicine at The University of Texas M. D. Anderson Cancer Center.

Many times the composition of herbal medications is unknown, as is the amount that equals an effective dose, said Marcus.  There is also a lack of governmental oversight on the contents, effectiveness and safety of herbal medicines.

Often, there are few or no scientific studies showing that the herbal medications work on the diseases they are said to treat, said Marcus. Current federal regulations do not require proof that herbal medications, which are classified as dietary supplements, are effective. Marcus said the classification of herbal medications as dietary supplements is misleading.

National surveys show that 8 percent of American over the age of 65 use herbal medications. However, nearly half of them do not tell their doctors about that use. Without that information, their physicians cannot make informed decisions about which medicines they should prescribe.

Although patients may be hesitant to disclose their use of herbal medications to physicians, it's important for doctors to be informed and knowledgeable about the use of herbal medications, said Marcus.  Physicians should also educate their patients about the use of herbal medications, such as potential side effects and drug interactions.

Surveys indicate that at least two-thirds of people over the age of 65 who take herbal medicine take at least one prescription medication on a regular basis. At the same time, these patients may be more likely to have drug interactions because of the way they metabolize drugs. Some commonly used herbal preparations such as ginger and St. John's wort can interfere with drug metabolism. There is also little information about the effects of herbal preparations on liver or kidney function, Marcus said.


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