The usual adult dosage of nicotinic acid is 1 to 2 grams two or three times a day. Doses should be individualized according to the patient's response. Start with one-half tablet (250 mg) as a single daily dose following the evening meal. The frequency of dosing and total daily dose can be increased every four to seven days until the desired LDL cholesterol and/or triglyceride level is achieved or the first-level therapeutic dose of 1.5 to 2 grams/day is reached. If the patient's hyperlipidemia is not adequately controlled after 2 months at this level, the dosage can then be increased at two to four week intervals to 3 grams/day (1 gram three times per day). In patients with marked lipid abnormalities, a higher dose is occasionally required, but generally should not exceed 6 grams/day.

Flushing of the skin appears frequently and can be minimized by pretreatment with aspirin or non-steroidal anti-inflammatory drugs. Tolerance to this flushing develops rapidly over the course of several weeks. Flushing, pruritus, and gastrointestinal distress are also greatly reduced by slowly increasing the dose of nicotinic acid and avoiding administration on an empty stomach.

Sustained-release (modified-release, timed-release) nicotinic acid preparations should not be substituted for equivalent doses of immediate-release (crystalline) nicotinic acid.