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Niacin overdose is unlikely if you take niacin only in the amount prescribed by your doctor. While it's not possible to overdose on niacin simply by eating too many niacin-rich foods, taking too much over-the-counter or prescription niacin can be dangerous.
You may have seen rumors about niacin on the Internet. The rumors falsely state that taking a large amount of niacin can flush the chemicals that show you've used marijuana out of your body before a drug test. No studies have shown that niacin can do this, and it can be very dangerous because a niacin overdose can cause severe liver damage.
Niacin overdose signs and symptoms include:
If you're concerned about a potential niacin overdose, talk to your doctor to make sure you're taking the correct amount. If you think you may have overdosed, seek medical attention immediately.
Katherine Zeratsky, R.D., L.D.
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