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1. obsolete term for nicotinamide and/or nicotinic acid;
2. obsolete term for pantothenic acid.
vitamin B3An obsolete term for:
(1) Nicotinic acid (niacin) and nicotinamide;
(2) Pantothenic acid.
n a water-soluble vitamin found in yeast, seeds, legumes, wild rice, and whole grains and available in three supplemental forms—niacin, inositol hexaniacinate, and niacin-amide. Has been used for deficien-cies (including low levels from isoniazid), high cholesterol (using niacin), intermittent claudication and Raynaud's phenomenon (using inositol hexaniacinate), osteoarthritis (using niacinamide), and diabetes (using niacinamide). High-dose niacin therapy may cause liver inflammation and is contraindicated for those with ulcers, gout, or excessive consumption of alcohol. Niacinamide is contraindicated for those taking anticonvulsant medications, and caution is advised for children and pregnant or lactating women, for whom the maximum daily dose is 35 mg. Also called