Medications and Drugs
Medical and Pharmacy Editor: Jay W. Marks, MD
GENERIC NAME: niacin, nicotinic acid, vitamin B3
BRAND NAME: Niacor, Niaspan,
Slo-Niacin
DRUG CLASS AND MECHANISM: Niacin (nicotinic acid, vitamin B3) is a
part of the normal diet that is essential to various chemical reactions in the
body. It is used medically to treat individuals with deficiency of niacin.
Advanced deficiency of niacin can lead to a condition called pellagra in which
individuals develop diarrhea, dermatitis and dementia. Niacin also
is used to reduce cholesterol and triglyceride levels in the blood. Specifically
it reduces bad cholesterol (LDL) and increases good cholesterol
(HDL). It is not clear how
niacin causes its effects on cholesterol and triglyceride levels, but it may be
by reducing the production of proteins that transport cholesterol and
triglycerides in the blood.
Niacin is available in immediate and slow-release forms (Niaspan,
Slo-Niacin). Natural sources of niacin include meat, poultry, liver, fish, nuts,
green vegetables, whole grains and potatoes.
PRESCRIPTION: Most formulations are available over the counter.
GENERIC AVAILABLE: Yes
PREPARATIONS: Tablets: 50, 100, 250, 500, and 750 mg. Capsules: 125, 250,
400, 500, 750, and 1000 mg
STORAGE: Store at room temperature between 15-30°C (59-86°F).
PRESCRIBED FOR: Niacin is used for treating niacin deficiency and elevated
blood cholesterol and/or triglyceride levels and for increasing HDL cholesterol.
DOSING: 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.
DRUG INTERACTIONS: Use of niacin with drugs that cause liver injury or muscle
injury may increase the occurrence of liver or muscle injury.
Niacin may increase blood glucose levels in diabetics. Therefore, medications
for controlling blood glucose levels may need to be adjusted when niacin is
taken by diabetic patients.
PREGNANCY: It is not known whether the high doses of niacin used in treating
elevated cholesterol levels are harmful to the fetus during pregnancy.
NURSING MOTHERS: Niacin is actively secreted in breast milk. Therefore,
nursing mothers taking niacin should avoid breast-feeding or discontinue niacin
in order to prevent the newborn from ingesting large amounts of niacin.
SIDE EFFECTS: The most common side effects of niacin are stomach upset,
flushing, headache, itching and tingling sensations of the extremities. Flushing
may be reduced by taking 325 mg of aspirin 30 minutes before the niacin and by
increasing the dose of niacin slowly. Drinking hot liquids or alcohol shortly
before or after niacin is taken may increase the occurrence of flushing.
Extended release formulations of niacin may cause flushing less frequently than
immediate release formulations. Rare cases of liver failure or muscle injury
have occurred from the use of niacin. Blood tests to monitor for liver injury
should be performed before niacin therapy begins, every 6-12 weeks for the first
year, and then occasionally thereafter. Niacin should be discontinued if liver
tests are greater than three times the upper limit of normal, are persistently
elevated, or accompanied by nausea, vomiting or weakness.
Reference: FDA Prescribing Information
Last Editorial Review: 10/21/2005
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
- Liver Blood Tests - Learn about liver blood tests used to detect liver damage disease such as fatty liver, cirrhosis, hepatitis, Tylenol liver damage, and more. This includes measuring the aminotransferases enzymes (AST and ALT levels)
- Night Sweats - Night sweats have many different causes. A doctors must take a complete medical history and order tests to find the cause of the underlying medical condition that is responsible for night sweats.
- Stroke - Learn about strokes symtoms like sudden numbness or weakness in the face, arms, or legs, confusion, vision problems, problems with walking or coordination, or severe headache.
Latest Medical News
Back to Medications Index
Cholesterol RSS