Niacin immediate release

Several different niacin formulations are available niacin immediate-release (IR), niacin sustained-release (SR), and niacin extended-release (ER).28,29 These formulations differ in terms of dissolution and absorption rates, metabolism, efficacy, and side effects. Limitations of niacin IR and SR are flushing and hepatotoxicity, respectively. These differences appear related to the dissolution and absorption rates of niacin formulations and its subsequent metabolism. Niacin IR is available by prescription (Niacor ) as well as a dietary supplement which is not regulated by the FDA.28 Currently, there are no FDA-approved niacin SR products, thus, all SR products are available only as dietary supplements. 

Niacin is indicated for hypertriglyceridemia and elevated LDL-C it is especially useful in patients with both hypertriglyceridemia and low HDL-C levels. There are two commonly available forms of niacin. Crystalline niacin (immediate-release or regular) refers to niacin tablets that dissolve quickly after ingestion. Sustained-release niacin refers to preparations that continuously release niacin for 6 to 8 hours after ingestion. Niaspan is the only preparation of niacin that has been approved by the FDA for treating dyslipidemia and that requires a prescription. 

Dosingof selected agents by class fibrate (gemfibrozil 600 mg twice a day) niacin (1.5-3 g/day of immediate-release product) statin (simvastatin 10-40 mg/day if glomerular filtration rate [GFR] <30 mL/min, 20-80 mg/day if GFR >30 mL/min) bile acid sequestrant (cholestyramine 4-16 g/day). 

The beneficial and adverse effects of nicotinic acid (niacin) have been reviewed (12). Standard nicotinic acid from an immediate-release formulation is metabolized primarily by conjugation, which results in a high frequency of flushing. Long-acting nicotinic acid is metabolized through the nicotinamide pathway, which results in less flushing but increases the risk of hepatotoxicity. Modified-release nicotinic acid, on the other hand, has a more balanced metabolism and causes fewer of both types of adverse effects. 

McKenney JM, Proctor JD, Harris S, Chinchili VM. A comparison of the efficacy and toxic effects of sustained-vs immediate-release niacin in hypercholesterolemic patients. JAMA 1994 271(9) 672-7. 

Morato Hernandez MDL, Del Sagrario Ichazo Cerro M, Alvarado Vega AG, Zamora Gonzalez J, Cardoso Saldana GC, Posadas Romero C. Immediate release niacin in the treatment of ischemic heart disease. Arch Inst Cardiol Mex 2000 70 367-76. 

The immediate-release formulation of phytosterols is made by Endurance Products Company, based outside of Portland, Oregon. Its Web site is www.endur.com. This is the same company that makes the best formulation of my favorite method of cholesterol control, niacin. Place orders outside the United States at www. endur.com click on Customer Service page. International Orders. Take two 450 mg tablets at the start of two major meals daily to block the absorption of cholesterol in the foods you eat, inhibit the recycling of bile made of cholesterol, and achieve a cholesterol reduction in your bloodstream of up to 10 percent. 

McKenney, J. M., Proctor, ]., Harris, S and Chinchili, V. (1994). A comparison of the efficacy and toKic effects of sustained- vs. immediate-release niacin in hypcrcholcstcrolemic patients, AMA 271, 672-677. 

Niacin is readily absorbed from the gastrointestinal tract. The peak serum concentration for an immediate release oral dosage form is usually seen within 45 min of niacin ingestion 4-5 h for an extended release tablet. Niacin is hepatically metabolized and widely distributed into body tissues. Niacin is renally excreted. Excess amounts of niacin, beyond daily needs, are excreted largely unchanged in the urine. The plasma half-life is 45 min. 

In low HDL, the primary target remains LDL according to the ATP III, but emphasis shifts to weight reduction, increased physical activity, and smoking cessation and, if drug therapy is required, to fibric acid derivatives and niacin. Niacin has the potential for the greatest increase in HDL, and the effect is more pronounced with regular or immediate-release forms than with sustained-release forms. ... 

A 64-year-old woman with familial hypercholesterolemia, peripheral arterial disease and recent coronary bypass surgery developed Achilles tendon xanthomas within several months of adding immediate-release niacin and cholestyramine to rosuvastatin [80]. 

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