Niacinamide

**Semantic type:** Organic Chemical|Pharmacologic Substance|Vitamin

**Definition:** The active form of vitamin B3 and a component of the coenzyme nicotinamide adenine dinucleotide (NAD). Niacinamide acts as a chemo- and radio-sensitizing agent by enhancing tumor blood flow, thereby reducing tumor hypoxia. This agent also inhibits poly(ADP-ribose) polymerases, enzymes involved in the rejoining of DNA strand breaks induced by radiation or chemotherapy.

**Synonyms:** - 3-Pyridinecarboxamide - NIACINAMIDE - Nicamid - Nicosedine - Nicotinamide - Nicotinamidum - Nicotinic Acid Amide - Nicotinic acid amide - Nicotylamide - Pellagra-Preventing Factor - Vitamin PP - Vitamin PP - niacinamide - nicotinamide