Niacin (most commonly used form is inositol hexaniacinate) and
niacinamide have different uses. Niacin is used for: cholesterol
lowering - decreasing total and LDL cholesterol by up to 25%,
triglycerides by up to 50%, and increasing HDL by up to 25%,
intermittent claudication, and may be helpful in Raynaud's
phenomenon. Niacinamide has shown promise for the treatment of osteoarthritis.
Sources
Niacin is made in the body from the amino acid tryptophan. Sources of
tryptophan are: meat, poultry, dairy products, fish - especially
turkey and milk. Sources of nicacin are: seeds, yeast, bran, peanuts
(with skins), wild rice, brown rice, whole wheat, barley, almonds,
and peas.
Therapeutic dosage
To lower cholesterol: 500 to 1000 mg three times daily.
Intermittent claudication: 2 grams daily, in divided doses
Raynauds phenomenon: up to 4 grams daily, in divided doses
Osteoarthritis: (niacinamide) 3 grams daily in five divided doses.
Safety concerns
Liver toxicity in doses greater than 500 mg daily (usually, however,
at doses greater than 3000 mg daily). Periodic liver function tests
(liver enzymes) must be performed at the therapeutic doses indicated.
Skin flushing can occur at doses greater than 100 mg. Other side
effects are stomach irritation, itching, and headache. Niacin (not
inositol hexaniacinate) can worsen glucose control in diabetics. If
you have liver disease, diabetes, stomach ulcers, or gout do not take
niacin unless under the supervision of your physician. The
sustained-release form of niacin has a greater incidence of liver
toxicity and is therefore not recommended. The maximum dose in
pregnancy or nursing mothers has not been established.
Interactions
If you take cholesterol lowering medications in the statin family, or
if you drink excessive amounts of alcohol, you should not take
niacin. If you take cholestyramine or colestipol, because of
absorption interactions, you should take nicain at a different time
of the day. If you take oral contraceptives, you may need more
niacin. Niacin can intefere with the absorption of isoniazid, and
should be used in this case only under the supervision of a
physician.