Niacin (Vitamin B-3)

BASIC INFORMATION

Niacin is also called Vitamin B-3.
Brand names:
Niacin Capsules
Niacin Extended-Release Capsules
Diacin(R)
Niac(R)
Nico-400(R)
Nicobid(R)
Nico-Span(R)
Tega-Span(R)
Niacin Extended-Release Tablets
Span-Niacin(R)
Niacin Oral Solution
Nicotex(R)
Niacin Tablets
Nicolar(R)
Available from natural sources? Yes
Available from synthetic sources? Yes
Prescription required? Yes, for high doses used for cholesterol
reduction.
Fat-soluble or water-soluble: Water-soluble

NATURAL SOURCES

Beef liver
Brewer's yeast
Chicken, white meat
Halibut
Peanuts
Pork
Salmon
Sunflower seeds
Swordfish
Tuna
Turkey
Veal

REASONS TO USE

Maintains normal function of skin, nerves, digestive system.

Reduces cholesterol and triglycerides in blood.

Corrects niacin deficiency.

Dilates blood vessels.

Treats vertigo (dizziness) and ringing in ears.

Prevents premenstrual headache.

Treats pellagra.

UNPROVED SPECULATED BENEFITS

Prevents heart attacks.

Treats or prevents motion sickness.

Alleviates mental illness, notably schizophrenia.

Cures depression.

Prevents migraine headaches.

Improves poor digestion.

Protects against pollutants and toxins.

Treats leprosy.

Stimulates sex drive.

WHO NEEDS ADDITIONAL AMOUNTS?

Anyone with inadequate caloric or nutritional dietary intake or increased nutritional requirements.

Older people (over 55 years).

Pregnant or breast-feeding women.

Those who abuse alcohol or other drugs.

People with a chronic wasting illness including malignancies, pancreatic insufficiency, cirrhosis of the liver, sprue.

Anyone who experiences excess stress for long periods or who have recently undergone surgery.

Athletes and workers who participate in vigorous physical activities.

Those with a portion of the gastrointestinal tract surgically removed.

People with recent severe burns or injuries.

Those with diabetes.

Infants born with errors of metabolism (congenital disorders due to chromosome abnormalities).

Anyone with hyperthyroidism.

DEFICIENCY SYMPTOMS

Early Symptoms:

Muscle weakness

General fatigue

Loss of appetite

Headaches

Swollen, red tongue

Skin lesions, including rashes, dry scaly skin, wrinkles, coarse skin texture

Nausea and vomiting

Dermatitis

Diarrhea

Irritability

Dizziness Late Symptoms of severe deficiency called pellagra:

Dementia

Death

UNPROVED SPECULATED SYMPTOMS

Acne

Poor circulation

Mental problems

LAB TESTS TO DETECT DEFICIENCY

Urinary N-1 methylnicotinamide.

Urinary 2--pyrindone/N-1 methylnicotinamide. Test results not always conclusive.

Abnormal-liver-function studies.

DOSAGE AND USAGE INFORMATION

Age	RDA
0-6 months	6mg
6-12 months	8mg
1-3 years	9mg
4-6 years	11mg
7-10 years	16mg
MALES
11-18 years	18mg
19-22 years	19mg
23-50 years	18mg
50+ years	16mg
FEMALES
11-14 years	15mg
15-22 years	14mg
23+ years	13mg
Pregnant +2mg
Lactating	+4mg

What this vitamin does:

Aids in release of energy from foods.

Helps synthesize DNA.

Becomes component of two co-enzymes (NAD and NADP), which are both necessary for utilization of fats, tissue respiration and production of sugars.

Miscellaneous information:

The body manufactures niacin from tryptophan, an amino acid.

Available as:

Tablets or capsules: Swallow whole with full glass of liquid. Don't chew or crush. Take with meals or 1 to 1-1/2 hours after meals unless otherwise directed by your doctor.

Extended-release capsules or tablets: Swallow whole with full glass of liquid. Don't chew or crush. Take with or immediately after food to decrease stomach irritation.

Oral solution: Dilute in at least 1/2 glass water or other liquid. Take with meals or 1 to 1-1/2 hours after meals unless otherwise directed by your doctor.

Injectable forms are administered by doctor or nurse.

A constituent of many multivitamin/mineral preparations.

Some forms available by generic name.

WARNINGS AND PRECAUTIONS

Don't take if you:

Are allergic to niacin or any niacin-containing vitamin mixtures.

Have impaired liver function.

Have an active peptic ulcer.

Consult your doctor if you have:

Diabetes.

Gout.

Gallbladder or liver disease.

Over age 55:

Response to drug cannot be predicted. Dose must be individualized.

Pregnancy:

Risk to fetus with high doses outweighs benefits. Do not use.

Breast-feeding:

Studies are inconclusive. Consult doctor about supplements.

Don't take megadoses.

Effect on lab tests:

Urinary catecholamine concentration may falsely elevate results.

Urine glucose (using Benedict's reagent) may produce false-positive reactions.

Falsely elevates blood sugar.

Falsely increases growth-hormone level in blood.

Falsely elevates blood uric acid with large daily doses.

Storage:

Store in cool, dry place away from direct light, but don't freeze.

Store safely out of reach of children.

Don't store in bathroom medicine cabinet. Heat and moisture may change action of vitamin.

Others:

High dosages over long periods may cause liver damage or aggravate a stomach ulcer.

OVERDOSE/TOXICITY

Signs and symptoms:
Body flush, nausea, vomiting, abdominal cramps, diarrhea,
weakness, lightheadedness, headache, fainting, sweating, high
blood sugar, high uric acid, heart rhythm disturbances,
jaundice.

What to do:

For symptoms of overdosage: Discontinue vitamin, and consult doctor. Also see ADVERSE REACTIONS OR SIDE EFFECTS section below.

For accidental overdosage (such as child taking entire bottle): Dial 911 (emergency), 0 for operator or your nearest Poison Control Center.

ADVERSE REACTIONS OR SIDE EFFECTS

Reaction or effect	What to do
Abdominal pain	Discontinue. Call doctor
	immediately.
Diarrhea	Discontinue. Call doctor when
	convenient.
Faintness	Discontinue. Call doctor
	immediately.
Headache	Discontinue. Call doctor when
	convenient.
"Hot" feeling, with skin flushed	Nothing.
in blush zone (always)
Jaundice (yellow skin and eyes)	Discontinue. Call doctor
	immediately.
Nausea or vomiting	Discontinue. Call doctor
	immediately.
Skin dryness	Discontinue. Call doctor when
	convenient.
Vomiting	Discontinue. Call doctor
	immediately.

INTERACTION WITH MEDICINE, VITAMINS OR MINERALS

Interacts with	Combined effect
Anti-diabetics	Decreases anti-diabetic
	effect.
Beta-adrenergic blockers	Lowers blood pressure to
	extremely low level.
Chenodiol	Decreases chenodiol effect.
Guanethidine	Increases guanethidine
	effect.
Isoniazid	Decreases niacin effect.
Mecamylamine	Lowers blood pressure to
	extremely low level.
Pargyline	Lowers blood pressure to
	extremely low level.

INTERACTION WITH OTHER SUBSTANCES

Tobacco decreases absorption. Smokers may require supplemental niacin.

Alcohol may cause extremely low blood pressure. Use caution.