Nicotinamie, also known as niacinamide and nicotinic acid amide, is the amide of nicotinic acid (vitamin B3). Nicotinamide is a water-soluble vitamin and is part of the vitamin B group. Nicotinic acid, also known as niacin, is converted to niacinamide in vivo, and though the two are identical in their vitamin functions, niacinamide does not have the same pharmacologic and toxic effects of niacin, which occur incidental to niacin's conversion. Thus niacinamide does not reduce cholesterol or cause flushing, although nicotinamide may be toxic to the liver at doses exceeding 3 g/day for adults. In cells, niacin is incorporated into nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), although the pathways for nicotinamide and nicotinic acid are very similar. NAD+ and NADP+ are coenzymes in a wide variety of enzymatic oxidation-reduction reactions.