Use of Niacin in the Prevention and Management of Hyperlipidemia

Anne White Robinson, DNS, RN; Helen L. Sloan, RN, CS, GNP, DNS; Gary Arnold, MD

In This Article

Implementation of Niacin Therapy

A major indication for the use of niacin is the combination of LDL levels between 100-129 mg/dL and low HDL levels (<60 mg/dL).[1] Combination therapy is often prescribed. The addition of an HMG CoA reductase inhibitor, e.g., lovastatin, pravastatin, or atorvastatin, to a niacin regimen is particularly effective. Schectman and Hiatt[2] noted that niacin-containing drug combinations are associated with a beneficial effect on lipid levels.

Niacin is also useful for the treatment of elevated serum TG levels. Management of hypertriglyceridemia among those with insulin-dependent diabetes mellitus, hypertension, and hyperlipidemia may include the use of niacin for TG levels >400 mg/dL. As indicated earlier, because of its adverse effect on insulin resistance and glucose tolerance, niacin must be administered with extreme caution to individuals with insulin-dependent diabetes and avoided entirely in patients with noninsulin-dependent diabetes.[49]

The common target dose of niacin for both primary and secondary management of heart disease is 1-2 g per day, although doses may range from 2-6 g per day. The administration of niacin in excess of 6 g per day is not recommended.[33,50] To reduce dose-related adverse side effects, niacin should be started at the lowest possible initial dose and gradually increased to achieve desired decreases in lipid levels. Patients must be carefully monitored throughout the period of time during which the dosage level is being increased. The patient education guide (Table 2) can assist the patient in taking niacin correctly and in patient follow-up.

Plain niacin is generally started at a strength of 50-100 mg t.i.d. The drug should be taken with meals. An alternative to the t.i.d. regimen is a beginning dose of 250 mg to be taken once a day after the evening meal. The starting regimen of niacin may be increased by 100-300 mg/day every 5-7 days. When an initial therapeutic level of 500 mg t.i.d. has been achieved, lipid levels should be measured to determine if LDL and HDL responses are acceptable. If not, a gradual increase in dose may be continued until a 2-3-g daily dose is reached.[1,33,42] Witztum[7] recommended that initial therapeutic doses of plain niacin should be maintained for 4-6 weeks, during which time liver function tests are performed and uric acid, glucose, and lipid levels measured. Thereafter, the niacin dose may be gradually increased on a monthly basis until the desired therapeutic effect is achieved. A lower daily dose of niacin (<2 g) used in combination with a statin may decrease the risk for elevations in glucose and uric acid as well as reduce the danger of hepatoxicity.[51] The dosage of plain niacin in combination therapy may be increased to 1000 mg t.i.d.[1]

The starting dose for extended-release niacin is 375 mg/day at bedtime. The nighttime administration of the extended-release form of niacin appears to decrease free fatty acid tranport to the liver and limit the usual nocturnal increase in plasma TG levels. For the patient with hyperlipidemia who requires drug therapy, the once-nightly administration of Niaspan® together with nighttime administration of a statin constitutes a convenient dosing schedule. Combination therapy with Niaspan® and a statin is equivalent to the combination of plain niacin and a statin in antilipid effectiveness.

As with plain niacin, dosing should proceed slowly. Starting doses of Niaspan® should be maintained for at least 1 week before being increased to 500 mg/day for the second week, and to 750 mg/day for the third week. When the dose of Niaspan® has reached 1000 mg/day it should be maintained for at least 3 weeks, after which it may be increased in 500-mg increments every 4 weeks. The maximum recommended dosage is 2000 mg/day.[33,54] Doses in excess of this level tend to aggravate side effects without any further improvement in lipid levels. Prior to beginning treatment with Niaspan®, and every 6-8 weeks during early adminstration, serum transaminase, glucose, and uric acid levels should be measured. Once therapeutic levels have been achieved, serum lipids and blood chemistries may be checked every 4-6 months for at least 1 year and periodically thereafter.