A common regimen in treating hyperlipoproteinemia, including hypercholesterolemia begins with 100 milligrams three times a day. This dose is gradually increased to an average of 1 gram three times a day to a maximum dose of 6 grams a day. This is increased by no more than 500 milligrams per 4 week period to a maximum of 2 - 1000 milligram tabs at bedtime. A parenteral route is only used when oral therapy is impossible. Regular, immediate release tablets peak in 45 minutes.
Food minimizes gastrointestinal upset, a low-fat meal is recommended.
Contraindications Hypersensitivity to niacin, active liver disease, arterial bleeding, and active peptic ulcer contraindicate the use of niacin. An increase in AST and alkaline phosphatase levels may occur, but severe hepatotoxicity is rare. Sustained release tablets have a higher incidence of hepatotoxicity. Modest hepatocellular injury occurred in a study of a 46 year old man after 1 month of niacin at 3 grams daily and resolved when therapy was discontinued. Ambylopia can also occur.