INTRODUCTION
Nicotinamide, also known as niacinamide, represents the water-soluble form of vitamin B3, while niacin, or nicotinic acid, constitutes its acidic counterpart. Nicotinamide plays a crucial role in our bodies by acting as a cofactor in enzymatic redox reactions, specifically facilitating the transfer of electrons in metabolic pathways. It is a precursor for biosynthesis of essential coenzymes involved in cellular energy production, DNA repair and other critical biochemical processes. It also inhibits PARP-1 and other molecules involved in cell signaling, which is essential for regulating DNA repair and maintaining cellular function.1 Insufficient intake of this vitamin from dietary sources can lead to pellagra, characterized by a triad of symptoms: dementia, dermatitis, and diarrhea. To avoid deficiency, the Office of Dietary Supplements within the National Institutes of Health recommends that adults consume at least 15 mg of nicotinamide per day. De novo synthesis and salvage pathways also contribute to the body's stores of this vitamin. Most individuals consume more than adequate amounts of nicotinamide daily, with the median reporting 37 mg per day, and only 4% of people consuming less than the recommended 15 mg per day.2 Although niacin and nicotinamide represent different forms of vitamin B3, they share similar end products and secondary metabolites (Figure 1). Both niacin and nicotinamide are precursors to the coenzymes nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP). Excess niacin or nicotinamide leads to increased NAD+ production, which is methylated to N-methylnicotinamide. N-methylnicotinamide is then further oxidized into N1-methyl-2-pyridone-5-carboxamide (2PY) and N1-methyl-4-pyridone-3-carboxamide (4PY) (Figure 1).3
Oral nicotinamide, which is used to avoid the common side effect of flushing seen with niacin, has a wide range of applications in dermatology including the treatment of blistering skin disorders, acne vulgaris, uremic pruritus, and chemoprevention of non-melanoma skin cancers (NMSC). Recent research has found an association between nicotinamide metabolites and increased
Oral nicotinamide, which is used to avoid the common side effect of flushing seen with niacin, has a wide range of applications in dermatology including the treatment of blistering skin disorders, acne vulgaris, uremic pruritus, and chemoprevention of non-melanoma skin cancers (NMSC). Recent research has found an association between nicotinamide metabolites and increased
