What are the side effects of niacin?

Dr. Darria Long Gillespie, MD
Emergency Medicine
Side effects may include flushing of the head and neck, itching, digestive symptoms, liver problems, and high blood sugar or uric acid. 

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Although there is no known toxicity in humans from natural sources of niacin, supplements and fortification can push you over your limit. Side effects, such as flushed skin, can occur in those who have ingested as little as 30 milligrams per day.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.