- What is niacin, and how does it work (mechanism of action)?
- What brand names are available for niacin?
- Is niacin available as a generic drug?
- Do I need a prescription for niacin?
- What are the side effects of niacin?
- What is the dosage for niacin?
- Which drugs or supplements interact with niacin?
- Is niacin safe to take if I'm pregnant or breastfeeding?
- What else should I know about niacin?
What is the dosage for niacin?
The recommended oral dose of immediate release niacin for treating high cholesterol levels in adults is 1-2 g two to three times daily. The maximum recommended dose is 6 g daily. When using extended release tablets, the maximum recommended dose is 2 g per day. Niacin should be started at low doses and increased slowly over several weeks. To avoid stomach upset, niacin should be taken with meals.
Extended release tablets should be swallowed whole and should not be crushed or chewed. Extended release formulations should not be substituted with equivalent doses of immediate release niacin since this leads to an overdose of niacin that may cause liver failure.
Pellagra may be treated with up to 500 mg per day of oral niacin.
Which drugs or supplements interact with niacin?
Use of niacin with drugs that cause liver or muscle injury, for example, lovastatin (Mevacor) or simvastatin (Zocor) may increase the occurrence of liver or muscle injury.
Niacin may increase blood glucose levels in individuals with diabetes. Therefore, medications for controlling blood glucose may need to be adjusted when niacin is taken by those with diabetes.
Bile acid sequestrants (for example, cholestyramine [Questran]) bind and prevent absorption of niacin. Administration of bile acid sequestrants and niacin should be separated by 4-6 hours.
Quick GuideLower Your Cholesterol, Save Your Heart
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