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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Limited Use [what does this mean?]
Generic drug name: niacin [vitamin B3] (NYE a sin)
Brand name(s): NICOLAR
GENERIC: available FAMILY: Vitamins
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Vitamins taken at the level that supplies normal body needs (not megadoses) do not pose a risk to the fetus or the nursing infant.

Facts About This Drug [top]

 

FOODS HIGH IN NIACIN (VITAMIN B3)
Beef, pork, liver, eggs, nuts, poultry, milk and dairy products (all are high in cholesterol and/or fat), fish, whole-grain and enriched breads and cereals, beans, peas, potatoes. Cooking destroys some niacin.  
3½ ounces calves’ liver 16.5 milligrams niacin
1 cup wheat flakes 14.7 milligrams niacin
4 ounces halibut 10.4 milligrams niacin
¼ cup peanuts 10.0...

 

FOODS HIGH IN NIACIN (VITAMIN B3)
Beef, pork, liver, eggs, nuts, poultry, milk and dairy products (all are high in cholesterol and/or fat), fish, whole-grain and enriched breads and cereals, beans, peas, potatoes. Cooking destroys some niacin.  
3½ ounces calves’ liver 16.5 milligrams niacin
1 cup wheat flakes 14.7 milligrams niacin
4 ounces halibut 10.4 milligrams niacin
¼ cup peanuts 10.0 milligrams niacin
3½ ounces roast turkey 7.7 milligrams niacin
1 slice whole wheat bread 6.0 milligrams niacin

Niacin, also called nicotinic acid or vitamin B3, and its derivative niacinamide, also called nicotinamide, are used by the body to help convert food to energy. Niacin is available in many types of foods (see box above), and a well-balanced diet with a variety of healthful foods should supply all the niacin that your body needs. The recommended dietary allowance (RDA) is 16 milligrams for men over the age of 50, and 14 milligrams for women over the age of 50.

Dietary deficiency of niacin, called pellagra, is rare. If you need to get more niacin, it is better to eat niacin-rich foods than to take a vitamin supplement. You should take niacin supplements to prevent and treat niacin deficiency only when your diet does not provide an adequate amount.

Niacin (nicotinic acid), but not niacinamide, has another use. It can be prescribed as part of a program to lower blood cholesterol or fat, which also includes a modified diet and exercise. The dose for this purpose, 300 milligrams or more, is much higher than the dose as a dietary supplement (10 to 20 milligrams). Taking niacin for this purpose is only an adjunct to weight reduction and exercise, not a substitute.

The adverse effects of niacin, such as blood vessel dilation, which produces intense flushing and itching of the face and upper part of the body, may limit the usefulness of this treatment. One aspirin taken 30 minutes before a dose of niacin may reduce this adverse effect.[1]

Niacin is not useful in treating schizophrenia or other mental disorders unrelated to niacin deficiency. It has not been proven effective in treating any blood vessel diseases nor in treating acne, leprosy, or motion sickness.

If you use niacin without a doctor’s supervision, do not exceed the RDA. Excess niacin, beyond what is needed each day, simply passes through you and is eliminated in the urine without being used by your body. Avoid taking extended-release forms of niacin, since these may damage your liver.

The British Expert Group on Vitamins and Minerals has found that:

Large doses of nicotinic acid [niacin] are associated with a number of adverse effects in man. These have been identified from the use of nicotinic acid in the treatment of hypercholesterolaemia. The effects reported include flushing, skin itching, nausea, vomiting and gastrointestinal disturbance. The effects are dose related and reversible on cessation of treatment. At higher intakes of nicotinic acid over long periods of time, liver dysfunction has been reported. Symptoms such as elevated liver enzymes, elevated bilirubin levels and jaundice have been observed.

Other adverse effects reported include hyperglycaemia and adverse ophthalmological effects such as blurred vision and cystoid macular oedema. No relevant animal data have been reported and the mechanism for nicotinic acid–induced toxicity is unclear.[2]

Before You Use This Drug [top]

Tell your doctor if you have or have had:

  • allergy to niacin or niacinamide
  • arterial bleeding or hemorrhage
  • glaucoma
  • gout
  • ulcer
  • liver disease
  • diabetes
  • low blood pressure
  • pregnancy or are breast-feeding

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Until you know how you react to this drug, do not drive or perform other activities requiring alertness. Niacin may cause dizziness or fainting.

How to Use This Drug [top]

  • 8Take with food or milk; check with your doctor if stomach upset continues.
  • Swallow extended-release capsules whole, or capsules may be opened and the contents mixed with applesauce, jelly, or ketchup, then swallowed without chewing.
  • If you miss a dose, take it as soon as you remember, but skip the dose if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

cholestyramine, COLESTID, colestipol, GLUCOPHAGE, lovastatin, metformin, MEVACOR, QUESTRAN.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • skin rash or itching
  • wheezing

Call your doctor if these symptoms continue:

  • warm feeling
  • skin flushing or redness, especially on face and neck
  • headache

With high oral doses:

  • unusually fast, slow, or irregular heartbeat
  • diarrhea
  • dizziness or faintness
  • dryness of skin or eyes
  • frequent urination
  • unusual thirst
  • joint pain
  • side, lower back, or stomach pain
  • swelling of feet or lower legs
  • fever
  • muscle aching or cramping
  • unusual tiredness or weakness
  • nausea or vomiting
  • peptic ulcer
  • itching

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

For high-dose therapy:

  • blood levels of uric acid

last reviewed May 31, 2021