Niacin Flush

Niacin flush is a common side effect of nicotinic acid (vitamin B3) supplementation, causing redness, warmth, itching, and tingling on the skin due to prostaglandin release and blood vessel dilation. Symptoms are typically mild to moderately uncomfortable and resolve within a few hours.

Niacin flush is a common and generally harmless side effect experienced when taking nicotinic acid (vitamin B3, niacin) supplements, particularly at higher doses. This reaction is characterized by a rapid onset of redness, warmth, itching, and tingling sensations on the skin, most commonly affecting the face, neck, and upper chest. The physiological mechanism involves the release of prostaglandins, which cause blood vessel dilation. The intensity of symptoms can vary from mild to moderately uncomfortable, typically resolving within a few hours. Although not typically dangerous, niacin flush can be unsettling for some individuals and may lead to cessation of niacin supplementation. Certain extended-release formulations and specific preparations have been developed to minimize or reduce the incidence and severity of niacin flush.