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Potency of these Alzheimer's pills might not match the label

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By , Executive Editor, Harvard Health Letter

illustration of a medication capsule casting a shadow onto a wall as a question mark

Here's an example of why you must be especially careful when selecting supplements: Harvard Medical School researchers say that galantamine, a plant extract used in prescription medications to treat Alzheimer's, is often mislabeled and sometimes contaminated with bacteria when it's sold as a dietary supplement. Scientists compared 11 brands of prescription generic galantamine and 10 brands of over-the-counter galantamine dietary supplements. "In the generic drug, the amount of galantamine listed on the label accurately represented the amount of galantamine in the pills and, importantly, no bacterial contamination was found. But 90% of galantamine dietary supplements contained an inaccurate amount of galantamine, ranging from less than 2% to 110% of the labeled quantity. Disturbingly, 30% were also contaminated with bacteria that could, if consumed at higher levels, cause diarrheal illnesses," says Dr. Pieter Cohen, the study's lead author and an associate professor of medicine at Harvard Medical School. The results were published online in a research letter Feb. 23, 2024, by JAMA. To ensure that you're getting safe supplements, Dr. Cohen urges you to look for certification seals from vetted independent third parties, such as the U.S. Pharmacopeia and NSF International's Certified for Sport program. And talk to your doctor before taking any dietary supplement.

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About the Author

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Heidi Godman, Executive Editor, Harvard Health Letter

Heidi Godman is the executive editor of the Harvard Health Letter. Before coming to the Health Letter, she was an award-winning television news anchor and medical reporter for 25 years. Heidi was named a journalism fellow … See Full Bio
View all posts by Heidi Godman

About the Reviewer

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Anthony L. Komaroff, MD, Editor in Chief, Harvard Health Letter

Dr. Anthony L. Komaroff is the Steven P. Simcox/Patrick A. Clifford/James H. Higby Professor of Medicine at Harvard Medical School, senior physician at Brigham and Women’s Hospital in Boston, and editor in chief of the Harvard … See Full Bio
View all posts by Anthony L. Komaroff, MD


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