DOUGLAS LABS - Niacinamide 500 mg - 100 Capsule(s) - NPN: 80014920 -- Niacin (vitamin B3) can be obtained from niacinamide, an amide of niacin that is typically well tolerated and not associated with causing a -flushing' reaction.Niacin occurs in the body as two metabolically active coenzymes, NAD (nicotinamide adenine