Now - Flush Free Niacin - 90 veggie Capsule(s) - NPN: 80006191 -- Many Niacin supplements cause a temporary Niacin flush or tingling red rash on the skin when taken in large doses. This flush-free Niacin is formulated to avoid such reactions. Inositol Hexanicotinate is a stable, non-flushing source of Niacin. This superior source, and lower potency of Niacin works to reduce the problems associated with mega doses of Niacin supplements. For extra strength, see our Niacin 500mg Flush-free version.