Click to expand Tap to zoom Niacinamide (500 mg) (100 Capsules) by Douglas Laboratories Sale $ 11.50 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart Niacinamide provides 500 mg of niacinamide per capsule. Dietary niacin can be obtained from niacinamide, an amide of niacin, which is typically well tolerated and not associated with causing a "flushing " reaction.