Niacin
(Nicotinic acid)
Niacin (Nicobid)
Nicotinic acid (Nicobid)
Niacin/Niacinamide
( NYE-ah-sin, nih-koh- TIN-ick AH-sid)
Pregnancy Category: C Niaspan Nico-400 Nicotinex Slo-Niacin Span-Niacin Tega-Span (Rx and OTC)
Niacinamide
Niacinamide
Niacin/Niacinamide
(nye-ah- SIN-ah-myd)
Pregnancy Category: C Papulex (Rx: Injection; OTC: Tablets)

Classification: Vitamin B complex

Action/Kinetics: Niacin (nicotinic acid) and niacinamide are water-soluble, heat-resistant vitamins prepared synthetically. Niacin (after conversion to the active niacinamide) is a component of the coenzymes nicotinamide-adenine dinucleotide and nicotinamide-adenine dinucleotide phosphate, which are essential for oxidation-reduction reactions involved in lipid metabolism, glycogenolysis, and tissue respiration. Deficiency of niacin results in pellagra, the most common symptoms of which are dermatitis, diarrhea, and dementia. In high doses niacin also produces vasodilation. Reduces serum cholesterol and triglycerides in types II, III, IV, and V hyperlipoproteinemia (mechanism unknown). Peak serum levels: 45 min; t 1/2: 45 min.

Uses: Prophylaxis and treatment of pellagra; niacin deficiency. Treat hyperlipidemia in clients not responding to either diet or weight loss. Reduce the risk of recurrent nonfatal MI in those with a history of MI and hypercholoesterolemia. Promote regression of atherosclerosis when combined with bile-binding resins. Niaspan is approved for increasing HDL cholesterol in dyslipidemia.

Contraindications: Severe hypotension, hemorrhage, arterial bleeding, liver dysfunction, active peptic ulcer. Use of the extended-release tablets and capsules in children.

Special Concerns: Extended-release niacin may be hepatotoxic. Use with caution in diabetics, gall bladder disease, in those who consume a large amount of alcohol, and clients with gout.

Side Effects: GI: N&V, diarrhea, peptic ulcer activation, abdominal pain. Dermatologic: Flushing, warm feeling, skin rash, pruritus, dry skin, itching and tingling feeling, keratosis nigricans. Other: Hypotension, headache, macular cystoid edema, amblyopia. NOTE: Megadoses are accompanied by serious toxicity including the symptoms listed in the preceding as well as liver damage, hyperglycemia, hyperuricemia, arrhythmias, tachycardia, and dermatoses.

Drug Interactions: Chenodiol / Effect of chenodiol Probenecid / Niacin may uricosuric effect of probenecid Sulfinpyrazone / Niacin uricosuric effect of sulfinpyrazone Sympathetic blocking agents / Additive vasodilating effects postural hypotension

How Supplied: Niacin: Capsule: 100 mg; Capsule, Extended Release: 125 mg, 250 mg, 400 mg, 500 mg, 750 mg; Elixir: 50 mg/5 mL; Tablet: 50 mg, 100 mg, 250 mg, 500 mg; Tablet, Extended Release: 500 mg, 750 mg, 1,000 mg. Niacinamide: Tablet: 50 mg, 100 mg, 500 mg

Dosage
Niacin ?Extended-Release Capsules, Tablets, Extended-Release Tablets, Capsules, Elixir Vitamin.
Adults: Up to 500 mg/day; pediatric: Up to 300 mg/day.
Antihyperlipidemic.
Adults, initial: 1 g t.i.d.; then: increase dose in increments of 500 mg/day q 2-4 weeks as needed. Maintenance: 1-2 g t.i.d. (up to a maximum of 8 g/day). Niaspan: Week 1, 375 mg hs; week 2, 500 mg; week 3, 750 mg hs; then, dose may be increased by no more than 500 mg in any 4- week period; do not give doses greater than 2,000 mg/day.
?IM, IV Pellagra.
Adults, IM: 50-100 mg 5 or more times/day. IV, slow: 25-100 mg 2 or more times/day. Pediatric, IV slow: Up to 300 mg/day.
Niacinamide ?Tablets Vitamin.
Adults: Up to 500 mg/day. Pediatric: Up to 300 mg/day. Capsules not recommended for use in children.