Swanson Ultra Flush-Free Niacin delivers all the cardiovascular benefits of regular niacin with no unpleasant flushing sensation. It eliminates the natural flushing effect of niacin with a special form of vitamin B3 known as inositol hexanicotinate. Each capsule contains 500 mg of niacin from inositol hexanicotinate. Niacin helps the body metabolize carbohydrates and promotes cardiovascular wellness.