Niacin flush may occur after taking large supplemental doses of niacin (vitamin B3). This vitamin is often used to treat high cholesterol levels. While uncomfortable, the warm, itchy, red skin is not dangerous.
This article reviews symptoms of niacin flush, how long symptoms last, and guidance to minimize skin flushing. Sodium Carbonate
High doses of supplemental niacin in the form of nicotinic acid bring about a reaction that causes the expansion of your capillaries. Capillaries are the smallest blood vessels that form a connection between the smallest arteries with the smallest veins. This expansion increases blood flow to the surface of the skin.
When blood flow increases on the skin’s surface, symptoms of flushing can occur, including:
Niacin skin flushing usually occurs within 30 minutes of taking supplemental niacin and tends to affect the face, neck, or upper chest.
While niacin flush can happen to anyone, people with darker skin tones may not experience reddening of the skin. Instead, the affected area may be discolored or darker than the rest of the skin.
Niacin flush is not harmful, though it may be unpleasant. It generally lasts just a short time.
Talk with a healthcare provider If you experience additional symptoms, such as dizziness, a drop in blood pressure, fatigue, nausea, heartburn, or blurred vision.
Stop taking high-dose niacin supplements if you are pregnant, and discuss appropriate supplements with a healthcare provider.
A niacin flush will usually last for 30 to 90 minutes. Flushing tends to be less severe and may decrease after continuous use of nicotinic acid supplements.
Flushing usually occurs after taking 30 to 50 milligrams (mg) or more of nicotinic acid.
When taken in higher doses of 1,000 to 3,000 mg per day, nicotinic acid can also cause more serious adverse effects.
Most people in the United States get more than the recommended daily intake (RDA) for niacin through the food they eat.
Niacin supplements are often prescribed to treat dyslipidemia (too high or low cholesterol levels). Older studies have shown that niacin may lower low-density lipoprotein (LDL) cholesterol, considered “unhealthy” cholesterol, levels and increase high-density lipoprotein (HDL) cholesterol, considered “good” cholesterol, levels. However, statins have become the standard medication used to treat high cholesterol levels.
Supplemental niacin may also reduce blood pressure, support brain health, and improve skin health.
No adverse effects have been reported from the consumption of naturally occurring niacin in foods.
Very high supplemental doses of niacin of 1,000 to 3,000 or more can cause more serious side effects. Most notably, liver toxicity is common with very high doses of niacin. Other side effects of very large doses may include decreased blood pressure, dizziness, fatigue, nausea, heartburn, or blurred vision.
If you experience these symptoms, contact a healthcare provider for guidance.
Experts have found some strategies to help minimize skin flushing. These include:
Niacin flush occurs after taking high doses of supplemental niacin. Symptoms include red, itchy skin around the face, neck, and upper chest. Niacin flush may be uncomfortable but is harmless and generally lasts 30 to 90 minutes.
Niacin flush typically occurs when taking niacin in doses of 30 to 50 milligrams (mg) or more. Niacin supplements are often used to treat high cholesterol levels.
Very high doses of 1,000 to 3,000 mg or more of niacin can cause more serious side effects, such as liver damage, decreased blood pressure, dizziness, fatigue, nausea, heartburn, or blurred vision.
Strategies that may help reduce the risk of niacin skin flushing include decreasing your dose, starting with a lower dose and slowly increasing, taking a different formulation, taking with food, or taking with aspirin.
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National Institutes of Health. Office of Dietary Supplements. Niacin fact sheet for health professionals.
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Moriarty PM, Backes J, Dutton JA, He J, Ruisinger JF, Schmelzle K. Apple pectin for the reduction of niacin-induced flushing. J Clin Lipidol. 2013;7(2):140-146. doi:10.1016/j.jacl.2012.11.005
Banka SS, Thachil R, Levine A, Lin H, Kaafarani H, Lee J. Randomized controlled trial of different aspirin regimens for reduction of niacin-induced flushing. Am J Health Syst Pharm. 2017;74(12):898-903. doi:10.2146/ajhp160219
By Brittany Poulson, MDA, RDN, CD, CDCES Brittany Poulson, MDA, RDN, CDCES, is a registered dietitian and certified diabetes care and education specialist.
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