Nicotinamide, also known as niacinamide, is the amide form of nicotinic acid (vitamin B3). It is a water-soluble vitamin essential for the synthesis of nicotinamide adenine dinucleotide (NAD+) and NADP+, coenzymes critical for cellular energy metabolism, DNA repair, and redox reactions. Found in foods like meat, fish, and grains, it is used as a dietary supplement to prevent pellagra and in cosmetics for anti-inflammatory and skin barrier benefits. Chemically stable under normal conditions, it participates in over 200 enzymatic reactions. Unlike nicotinic acid, it does not cause flushing. It is produced industrially via oxidation of nicotine or from 3-cyanopyridine hydrolysis.