Your body uses niacin to turn the food you eat into energy, produce certain hormones and keep your skin, nerves and digestive system working properly. Two different types of niacin are available as supplements: nicotinic acid and niacinamide, also known as nicotinamide. Only nicotinic acid helps to lower cholesterol when taken at high dosages under the supervision of a doctor.
Recommended Dietary Allowance
Adults should aim to get most of their recommended dietary allowance, or RDA, for niacin from food. Men need 16 mg per day, women need 13 mg per day, pregnant women need 18 mg per day, and breastfeeding women need 17 mg per day. You can take supplements to help you meet this recommended intake, but don't exceed the tolerable upper intake level of 35 mg per day for adults unless you do so under a doctor's supervision.
Cholesterol-Lowering Dosage
The dosages of nicotinic acid used to treat high cholesterol and high triglycerides are well above the RDA. Your doctor will determine the appropriate dose for your treatment, and you shouldn't exceed it. Anything over 50 mg of niacin per day is considered a high dosage, and cholesterol-lowering doses can go as high as 9 g per day, although your doctor will prescribe the lowest effective dosage.
Side Effects
High doses of nicotinic acid cause flushing, making the skin on your chest and face red and causing a tingling or burning sensation. Other side effects include muscle cramps or pain, dizziness, chills, gas, diarrhea, nausea, insomnia, vomiting, dry skin, skin rashes, blurred vision, uneven heartbeat, ulcers, liver damage, and flare-ups of gout if you have this condition. Taking aspirin 30 minutes before your niacin dosage can limit the flushing associated with this supplement.
Considerations
Do not take doses of niacin above the tolerable upper intake level unless prescribed by your doctor. Do not take a different formulation of niacin than the one prescribed, as timed-release and immediate-release niacin doses are different. Niacin may react with antibiotics, blood thinners, diabetes medication, alpha blockers, blood pressure medication and nicotine patches.
