Side effect of niacin

On call: Niacin for cholesterol

On call

Niacin for cholesterol

Published: January, 2007

Q. I hope you can clear up some family confusion. My doctor gave me a prescription for Niaspan, but my wife found the same medication, niacin, at the supermarket at a much lower price. Is it a drug or a vitamin?

A. Niacin is a natural substance “” in fact, it’s vitamin B3. Like other vitamins, it’s required to keep the metabolism working properly. But the recommended dietary allowance (RDA) for B3 is only 18 mg a day, far less than the amount needed to improve cholesterol levels. Still, any dose of niacin can be sold as a “dietary supplement” without a doctor’s prescription and without FDA oversight.

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9 Science-Based Benefits of Niacin (Vitamin B3)

1. Lowers LDL Cholesterol

Niacin has been used since the 1950s to treat high cholesterol (8).

In fact, it can lower levels of “bad” LDL cholesterol by 5–20% (9, 10).

However, niacin is not the primary treatment for high cholesterol due to its possible side effects (11).

Rather, it’s primarily used as a cholesterol-lowering treatment for people who can’t tolerate statins (12).

2. Increases HDL Cholesterol

In addition to lowering “bad” LDL cholesterol, niacin also raises “good” HDL cholesterol.

Studies show that niacin raises HDL levels by 15–35% (9).

3. Lowers Triglycerides

Niacin can also lower triglycerides by 20–50% (9).

It does this by stopping the action of an enzyme that’s involved in triglyceride synthesis (1).

Consequently, this lowers the production of both LDL and very low-density lipoprotein (VLDL).

Therapeutic doses are needed to achieve these effects on cholesterol and triglyceride levels (1).

4. May Help Prevent Heart Disease

Niacin’s effect on cholesterol may help prevent heart disease — but newer research suggests an additional mechanism by which it benefits your heart.

It can help reduce oxidative stress and inflammation, both of which are involved in atherosclerosis, or the hardening of your arteries (1).

Some research indicates that niacin therapy — either alone or in combination with statins — could help lower the risk of health problems related to heart disease (13).

However, results are mixed.

A recent review concluded that niacin therapy doesn’t significantly help reduce the risk of heart attack, stroke or death from heart disease in people with heart disease or those at a high risk (12).

5. May Help Treat Type 1 Diabetes

Type 1 diabetes is an autoimmune disease in which your body attacks and destroys insulin-creating cells in your pancreas.

There’s research to suggest that niacin could help protect those cells and possibly even lower the risk of type 1 diabetes in at-risk children (2, 14).

However, for people with type 2 diabetes, the role of niacin is more complicated.

On the one hand, it can help lower the high cholesterol levels that are often seen in people with type 2 diabetes (15).

On the other, it has the potential to increase blood sugar levels.

As a result, people with diabetes who take niacin to treat high cholesterol also need to monitor their blood sugar carefully (16).

6. Boosts Brain Function

Your brain needs niacin — as a part of the coenzymes NAD and NADP — to get energy and function properly.

In fact, brain fog and even psychiatric symptoms are associated with niacin deficiency (16).

Some types of schizophrenia can be treated with niacin, as it helps undo the damage to brain cells that occurs as a result of deficiency (17).

Preliminary research shows that it could also help keep the brain healthy in cases of Alzheimer’s disease. However, results are mixed (18, 19).

7. Improves Skin Function

Niacin helps protect skin cells from sun damage, whether it’s used orally or applied as a lotion (20).

Recent research suggests it may help prevent some types of skin cancer as well (21).

One study found that taking 500 mg of nicotinamide — a form of niacin — twice daily reduced rates of non-melanoma skin cancer among high-risk individuals (22).

8. May Reduce Symptoms of Arthritis

In one preliminary study, niacin helped ease some symptoms of osteoarthritis, improving joint mobility and reducing the need for nonsteroidal anti-inflammatory drugs (NSAIDs) (23).

Another study in lab rats found that an injection with the vitamin reduced inflammation related to arthritis (24).

Although this is promising, more research is needed.

9. Treats Pellagra

Severe niacin deficiency causes a condition called pellagra (6, 25).

Thus, taking a niacin supplement is the main treatment for pellagra.

Niacin deficiency is rare in industrialized countries. However, it may occur alongside other diseases, such as alcoholism, anorexia or Hartnup disease.

Summary Niacin can help treat many conditions. Most notably, it helps raise “good” HDL cholesterol levels while lowering “bad” LDL cholesterol and triglycerides.

Niaspan

SIDE EFFECTS

Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice.

Clinical Studies Experience

In the placebo-controlled clinical trials database of 402 patients (age range 21-75 years, 33% women, 89% Caucasians, 7% Blacks, 3% Hispanics, 1% Asians) with a median treatment duration of 16 weeks, 16% of patients on NIASPAN and 4% of patients on placebo discontinued due to adverse reactions. The most common adverse reactions in the group of patients treated with NIASPAN that led to treatment discontinuation and occurred at a rate greater than placebo were flushing (6% vs. 0%), rash (2% vs. 0%), diarrhea (2% vs. 0%), nausea (1% vs. 0%), and vomiting (1% vs. 0%). The most commonly reported adverse reactions (incidence > 5% and greater than placebo) in the NIASPAN controlled clinical trial database of 402 patients were flushing, diarrhea, nausea, vomiting, increased cough and pruritus.

In the placebo-controlled clinical trials, flushing episodes (i.e., warmth, redness, itching and/or tingling) were the most common treatment-emergent adverse reactions (reported by as many as 88% of patients) for NIASPAN. Spontaneous reports suggest that flushing may also be accompanied by symptoms of dizziness, tachycardia, palpitations, shortness of breath, sweating, burning sensation/skin burning sensation, chills, and/or edema, which in rare cases may lead to syncope. In pivotal studies, 6% (14/245) of NIASPAN patients discontinued due to flushing. In comparisons of immediate-release (IR) niacin and NIASPAN, although the proportion of patients who flushed was similar, fewer flushing episodes were reported by patients who received NIASPAN. Following 4 weeks of maintenance therapy at daily doses of 1500 mg, the incidence of flushing over the 4-week period averaged 8.6 events per patient for IR niacin versus 1.9 following NIASPAN.

Other adverse reactions occurring in ≥ 5% of patients treated with NIASPAN and at an incidence greater than placebo are shown in Table 2 below.

Table 2: Treatment-Emergent Adverse Reactions by Dose Level in ≥ 5% of Patients and at an Incidence Greater than Placebo; Regardless of Causality Assessment in Placebo- Controlled Clinical Trials

Placebo-Controlled Studies
NIASPAN
Recommended Daily Maintenance Doses †
Placebo
(n = 157) %
500 mg‡
(n = 87) %
1000 mg
(n = 110) %
1500 mg
(n = 136) %
2000 mg
(n = 95) %
Gastrointestinal Disorders
Diarrhea 13 7 10 10 14
Nausea 7 5 6 4 11
Vomiting 4 0 2 4 9
Respiratory
Cough, Increased 6 3 2 < 2 8
Skin and Subcutaneous Tissue Disorders
Pruritus 2 8 0 3 0
Rash 0 5 5 5 0
Vascular Disorders
Flushing* 19 68 69 63 55
Note: Percentages are calculated from the total number of patients in each column.
† Adverse reactions are reported at the initial dose where they occur.
@ Pooled results from placebo-controlled studies; for NIASPAN, n = 245 and median treatment duration = 16 weeks. Number of NIASPAN patients (n) are not additive across doses.
‡ The 500 mg/day dose is outside the recommended daily maintenance dosing range .
& 10 patients discontinued before receiving 500 mg, therefore they were not included.

In general, the incidence of adverse events was higher in women compared to men.

Atherothrombosis Intervention in Metabolic Syndrome with Low HDL/High Triglycerides: Impact on Global Health Outcomes (AIM-HIGH)

In AIM-HIGH involving 3414 patients (mean age of 64 years, 15% women, 92% Caucasians, 34% with diabetes mellitus) with stable, previously diagnosed cardiovascular disease, all patients received simvastatin, 40 to 80 mg per day, plus ezetimibe 10 mg per day if needed, to maintain an LDL-C level of 40-80 mg/dL, and were randomized to receive NIASPAN 1500-2000 mg/day (n=1718) or matching placebo (IR Niacin, 100-150 mg, n=1696). The incidence of the adverse reactions of “blood glucose increased” (6.4% vs. 4.5%) and “diabetes mellitus” (3.6% vs. 2.2%) was significantly higher in the simvastatin plus NIASPAN group as compared to the simvastatin plus placebo group. There were 5 cases of rhabdomyolysis reported, 4 (0.2%) in the simvastatin plus NIASPAN group and one ( < 0.1%) in the simvastatin plus placebo group .

Postmarketing Experience

Because the below reactions are reported voluntarily from a population of uncertain size, it is generally not possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

The following additional adverse reactions have been identified during post-approval use of NIASPAN:

Hypersensitivity reactions, including anaphylaxis, angioedema, urticaria, flushing, dyspnea, tongue edema, larynx edema, face edema, peripheral edema, laryngismus, and vesiculobullous rash; maculopapular rash; dry skin; tachycardia; palpitations; atrial fibrillation; other cardiac arrhythmias; syncope; hypotension; postural hypotension; blurred vision; macular edema; peptic ulcers; eructation; flatulence; hepatitis; jaundice; decreased glucose tolerance; gout; myalgia; myopathy; dizziness; insomnia; asthenia; nervousness; paresthesia; dyspnea; sweating; burning sensation/skin burning sensation; skin discoloration, and migraine.

Clinical Laboratory Abnormalities

Chemistry: Elevations in serum transaminases , LDH, fasting glucose, uric acid, total bilirubin, amylase and creatine kinase, and reduction in phosphorus.

Hematology: Slight reductions in platelet counts and prolongation in prothrombin time .

Read the entire FDA prescribing information for Niaspan (Niacin)

Niacin

Medically reviewed by Sanjai Sinha, MD Last updated on Mar 16, 2019.

  • Overview
  • Side Effects
  • Dosage
  • Professional
  • Interactions
  • More

What is niacin?

Niacin, also called nicotinic acid, is a B vitamin (vitamin B3). It occurs naturally in plants and animals, and is also added to many foods as a vitamin supplement. It is also present in many multiple vitamins and nutritional supplements.

Niacin is used to lower blood levels of “bad” cholesterol (low-density lipoprotein, or LDL) and triglycerides, and increase levels of “good” cholesterol (high-density lipoprotein, or HDL).

Niacin may also be used for purposes not listed in this medication guide.

Important Information

You should not take niacin if you have severe liver disease, a stomach ulcer, or active bleeding.

Niacin can cause certain side effects, such as flushing (warmth, itching, redness, or tingly feeling under your skin). These effects can be made worse if you drink alcohol or hot beverages shortly after you take this medicine. These effects should disappear over time as you keep taking the medication.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Avoid taking colestipol (Colestid) or cholestyramine (Locholest, Prevalite, Questran) at the same time you take niacin. If you take either of these other medications, take them at least 4 to 6 hours before or after you take this medicine.

Niacin is only part of a complete program of treatment that may also include diet, exercise, weight control, and other medications. Follow your diet, medication, and exercise routines very closely.

Before taking this medicine

You should not take niacin if you are allergic to it.

To make sure you can safely take niacin, tell your doctor if you have ever had:

  • severe liver disease;

  • a stomach ulcer; or

  • active bleeding.

Tell your doctor if you have ever had:

  • liver disease;

  • heart disease, chest pain (angina);

  • gout; or

  • diabetes.

It is not known whether niacin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

You should not breastfeed while using this medicine.

Niacin is not approved for use by anyone younger than 18 years old.

How should I take niacin ?

Use niacin exactly as directed on the label, or as prescribed by your doctor. Read all medication guides or instruction sheets.

Niacin can cause flushing (warmth, itching, redness, or tingly feeling under your skin). These effects should disappear over time as you keep taking the medicine. Flushing may be worse if you drink alcohol or hot beverages shortly after taking niacin.

Swallow the capsule or tablet whole and do not crush, chew, break, or open it.

Your dose needs may change if you switch to a different brand, strength, or form of this medicine. Avoid medication errors by using only the form and strength your doctor prescribes.

If you stop taking niacin for any length of time, talk with your doctor before starting the medication again. You may need to restart the medication at a lower dose.

This medicine can affect the results of certain medical tests. Tell any doctor who treats you that you are using this medicine.

Niacin is only part of a complete treatment program that may also include diet, exercise, and weight control. Follow your diet, medication, and exercise routines very closely.

Your doctor may recommend you take aspirin or an NSAID (such as ibuprofen, Advil, or Aleve) to help prevent flushing. Keep using these medicines for as long as your doctor has prescribed.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking niacin ?

Avoid drinking alcohol. It may increase your risk of liver damage, and can also worsen the flushing effects of niacin.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy.

Avoid eating foods high in fat or cholesterol, or niacin will not be as effective.

Niacin side effects

Get emergency medical help if you have signs of an allergic reaction to niacin: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;

  • irregular heartbeats;

  • severe warmth or redness under your skin;

  • vision problems; or

  • jaundice (yellowing of the skin or eyes).

Common niacin side effects may include:

  • flushing (sudden warmth, redness, or tingly feeling);

  • upset stomach, vomiting, diarrhea;

  • abnormal liver function tests;

  • itching, dry skin;

  • skin discoloration; or

  • headache.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect niacin?

Tell your doctor about all your other medicines, especially:

  • statin cholesterol medication;

  • heart or blood pressure medication; or

  • other medicines that lower blood pressure.

This list is not complete. Other drugs may interact with niacin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use niacin only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Copyright 1996-2020 Cerner Multum, Inc. Version: 9.01.

Related questions

  • How long does niacin stay in the human system?

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  • Niacin Capsules and Tablets
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Other brands: Niaspan, Niacor, Slo-Niacin, Nicotinex

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Overview

Vitamin B3 (Niacin)

Also listed as:

Table of Contents > Supplements > Vitamin B3 (Niacin)

Overview Dietary Sources Available Forms How to Take It Precautions Possible Interactions Supporting Research

Vitamin B3 is one of 8 B vitamins. It is also known as niacin (nicotinic acid) and has 2 other forms, niacinamide (nicotinamide) and inositol hexanicotinate, which have different effects from niacin.

All B vitamins help the body convert food (carbohydrates) into fuel (glucose), which the body uses to produce energy. These B vitamins, often referred to as B-complex vitamins, also help the body use fats and protein. B-complex vitamins are needed for a healthy liver, healthy skin, hair, and eyes, and to help the nervous system function properly.

Niacin also helps the body make various sex and stress-related hormones in the adrenal glands and other parts of the body. Niacin helps improve circulation, and it has been shown to suppress inflammation.

All the B vitamins are water-soluble, meaning that the body does not store them.

You can meet all of your body’s needs for B3 through diet. It is rare for anyone in the developed world to have a B3 deficiency. In the U.S., alcoholism is the main cause of vitamin B3 deficiency.

Symptoms of mild B3 deficiency include:

  • Indigestion
  • Fatigue
  • Canker sores
  • Vomiting
  • Poor circulation
  • Depression

Severe deficiency can cause a condition known as pellagra. Pellagra is characterized by cracked, scaly skin, dementia, and diarrhea. It is generally treated with a nutritionally balanced diet and niacin supplements. Niacin deficiency also causes burning in the mouth and a swollen, bright red tongue.

Very high doses of B3, available by prescription, have been studied to prevent or improve symptoms of the following conditions. However, at high doses niacin can be toxic. You should not take doses higher than the Recommended Daily Allowance (RDA) except under your doctor’s supervision. Researchers are trying to determine if inositol hexanicotinate has similar benefits without serious side effects. But results are inconclusive.

High cholesterol

Niacin, but not niacinamide, has been used since the 1950s to lower elevated LDL (bad) cholesterol and triglyceride (fat) levels in the blood. However, side effects can be unpleasant and even dangerous. High doses of niacin cause:

  • Flushing of the skin
  • Stomach upset (which usually subsides within a few weeks)
  • Headache
  • Dizziness
  • Blurred vision
  • An increased risk of liver damage

A time-release form of niacin reduces flushing. But long-term use is associated with liver damage. In addition, niacin can interact with other cholesterol-lowering medicines. You should not take niacin at high doses without your doctor’s supervision.

Atherosclerosis and heart disease

In one study, men with existing heart disease slowed down the progression of atherosclerosis by taking niacin along with colestipol. They experienced fewer heart attacks and deaths, as well.

In another study, people with heart disease and high cholesterol who took niacin along with simvastatin (Zocor) had a lower risk of having a first heart attack or stroke. Their risk of death was also lower. In another study, men who took niacin alone seemed to reduce the risk of having a second heart attack, although it did not reduce the risk of death.

Diabetes

In type 1 diabetes, the body’s immune system mistakenly attacks the cells in the pancreas that make insulin, eventually destroying them. Niacinamide may help protect those cells for a time. More research is needed.

Researchers have also looked at whether high-dose niacinamide might reduce the risk of type 1 diabetes in children at risk for the disease. One study found that it did. But another, larger study found it did not protect against developing type 1 diabetes. More research is needed.

The effect of niacin on type 2 diabetes is more complicated. People with type 2 diabetes often have high levels of fats and cholesterol in the blood. Niacin, often along with other medications, can lower those levels. However, niacin may also raise blood sugar levels, which is particularly dangerous for someone with diabetes. For that reason, if you have diabetes, you should take niacin only under the direction of your doctor, and you should be carefully monitored for high blood sugar.

Osteoarthritis

One preliminary study suggested that niacinamide may improve arthritis symptoms, including increasing joint mobility and reducing the amount of non-steroidal anti-inflammatory drugs (NSAIDs) needed. More research is needed.

Other

Alzheimer disease: Population studies show that people who get higher levels of niacin in their diet have a lower risk of Alzheimer disease. No studies have evaluated niacin supplements, however.

Cataracts: One large population study found that people who got a lot of niacin in their diets had a lower risk of developing cataracts.

Skin conditions: Researchers are studying topical forms of niacin as treatments for rosacea, aging, and prevention of skin cancer, although it is too early to know whether it is effective.

Although there is no evidence that it helps treat any of these conditions, researchers are also studying the use of vitamin B3 in treating:

  • ADHD
  • Migraines
  • Dizziness
  • Depression
  • Motion sickness
  • Alcohol dependence

Dietary Sources

The best food sources of vitamin B3 are:

  • Beets
  • Brewer’s yeast
  • Beef liver
  • Beef kidney
  • Fish
  • Salmon
  • Swordfish
  • Tuna
  • Sunflower seeds
  • Peanuts

Bread and cereals are usually fortified with niacin. In addition, foods that contain tryptophan, an amino acid the body coverts into niacin, include poultry, red meat, eggs, and dairy products.

Available Forms

Vitamin B3 is available in several different supplement forms:

  • Niacinamide
  • Niacin
  • Inositol hexaniacinate.

Niacin is available as a tablet or capsule in both regular and timed-release forms. The timed-release tablets and capsules may have fewer side effects than regular niacin. However, the timed-release versions are more likely to cause liver damage. Regardless of which form of niacin you are using, doctors recommend periodic liver function tests when using high doses (above 100 mg per day) of niacin.

How to Take It

Generally, high doses of niacin are used to control specific diseases. Such high doses must be prescribed by a doctor who will increase the amount of niacin slowly, over the course of 4 to 6 weeks. Take niacin with meals to avoid stomach irritation.

Daily recommendations for niacin in the diet of healthy individuals are:

Pediatric

Adult

  • Men, 19 years and older: 16 mg (RDA)
  • Women, 19 years and older: 14 mg (RDA)
  • Pregnant women: 18 mg (RDA)
  • Breastfeeding women: 17 mg (RDA)

Precautions

Because of the potential for side effects and interactions with medications, you should take dietary supplements only under the supervision of a knowledgeable health care provider. Side effects may include diarrhea, headache, stomach discomfort, and bloating.

High doses (50 mg or more) of niacin can cause side effects. The most common side effect is called “niacin flush,” which is a burning, tingling sensation in the face and chest, and red or flushed skin. Taking an aspirin 30 minutes prior to the niacin may help reduce this symptom.

At very high doses, used to lower cholesterol and treat other conditions, liver damage and stomach ulcers can occur. Your doctor will regularly check your liver function through a blood test.

People with a history of liver disease, kidney disease, or stomach ulcers should not take niacin supplements. Those with diabetes or gallbladder disease should do so only under the close supervision of their doctors.

Stop taking niacin or niacinamide at least 2 weeks before a scheduled surgery.

Niacin and niacinamide may make allergies worse by increasing histamine.

People with low blood pressure should not take niacin or niacinamide because they may cause a dangerous drop in blood pressure. DO NOT take niacin if you have a history of gout.

People with coronary artery disease or unstable angina should not take niacin without their doctor’s supervision, as large doses can raise the risk of heart rhythm problems.

Taking any one of the B vitamins for a long period of time can result in an imbalance of other important B vitamins. For this reason, you may want to take a B-complex vitamin, which includes all the B vitamins.

Possible Interactions

Because of its impact on the liver, vitamin B3 can interact with several medications. If you are currently taking medications, or regularly drink alcohol, you should not use niacin without talking to your health care provider first. Below is a partial list of medications that may interact with vitamin B3.

Antibiotics, tetracycline: Niacin should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. All vitamin B complex supplements act in this way and should be taken at different times from tetracycline.

Aspirin: Taking aspirin before taking niacin may reduce flushing from niacin. But take it only under your doctor’s supervision.

Anti-seizure medications: Phenytoin (Dilantin) and valproic acid (Depakote) may cause niacin deficiency in some people. Taking niacin with carbamazepine (Tegretol) or mysoline (Primidone) may increase levels of these medications in the body.

Anticoagulants (blood thinners): Niacin may make the effects of these medications stronger, increasing the risk of bleeding.

Blood pressure medications, alpha-blockers: Niacin can make the effects of medications taken to lower blood pressure stronger, leading to the risk of low blood pressure.

Cholesterol-lowering medications: Niacin binds the cholesterol-lowering medications known as bile-acid sequestrants and may make them less effective. For this reason, niacin and these medications should be taken at different times of the day. Bile-acid sequestrants include colestipol (Colestid), colesevelam (Welchol), and cholestyramine (Questran).

Statins: Some scientific evidence suggests that taking niacin with simvastatin (Zocor) appears to slow the progression of heart disease. However, the combination may also increase the likelihood for serious side effects, such as muscle inflammation or liver damage.

Diabetes medications: Niacin may increase blood sugar levels. People taking insulin, metformin (Glucophage), glyburide (Dibeta, Micronase), glipizide (Glucotrol), or other medications used to treat high blood glucose levels should monitor their blood sugar levels closely when taking niacin supplements.

Isoniazid (INH): INH, a medication used to treat tuberculosis, may cause a niacin deficiency.

Nicotine patches: Using nicotine patches with niacin may worsen or increase the risk of flushing associated with niacin.

These medications may lower levels of niacin in the body:

  • Azathioprine (Imuran)
  • Chloramphenicol (Chloromycetin)
  • Cycloserine (Seromycin)
  • Fluorouracil
  • Levodopa and carbidopa
  • Mercaptopurine (Purinethol)

Supporting Research

AIM-HIGH Investigators. The role of niacin in raising high-density lipoprotein cholesterol to reduce cardiovascular events in patients with atherosclerotic cardiovascular disease and optimally treated low-density lipoprotein cholesterol Rationale and study design. The Atherothrombosis Intervention in Metabolic syndrome with low HDL/high triglycerides: Impact on Global Health outcomes (AIM-HIGH). Am Heart J. 2011 Mar;161(3):471-477.e2.

Bissett DL, Oblong JE, Berge CA, et al. Niacinamide: A B vitamin that improves aging facial skin appearance. Dermatol Surg. 2005;31:860-865; discussion 865.

Cumming RG, Mitchell P, Smith W. Diet and cataract: the Blue Mountains Eye Study. Ophthalmology. 2000;107(3):450-456.

Draelos ZD, Ertel K, Berge C, et al. Niacinamide-containing facial moisturizer improves skin barrier and benefits subjects with rosacea. Cutis. 2005;76:135-141.

Elam M, Hunninghake DB, Davis KB, et al. Effects of niacin on lipid and lipoprotein levels and glycemic control in patients with diabetes and peripheral arterial disease: the ADMIT study: a randomized trial. Arterial Disease Multiple Intervention Trial. JAMA. 2000;284:1263-1270.

Ginsberg HN, reyes-Soffer G. Niacin: a long history, but a questionable future. Curr Opin Lipidol. 2013;24(6):475-9.

Goldberg A, Alagona P, Capuzzi DM, et al. Multiple-dose efficacy and safety of an extended-release form of niacin in management of hyperlipidemia. Am J Cardiol. 2000;85:1100-1105.

Guyton JR. Niacin in cardiovascular prevention: mechanisms, efficacy, and safety. Curr Opin Lipidol. 2007 Aug;18(4):415-420.

Jones KW. Do patients on statins also need niacin? JAAPA. 2013;26(7):9-10.

Sahebkar A. effect of niacin on endothelial function: a systematic review and meta-analysis of randomized controlled trials. Vasc Med. 2014;19(1):54-66.

Song WL, FitzGerald GA. Niacin, an old drug with a new twist. J Lipid Res. 2013;54(10):2486-94.

Surjana D. Damian DL. Nicotinamide in dermatology and photoprotection. Skinmed. 2011;9(6):360-365.

Torkos S. Drug-nutrient interactions: a focus on cholesterol-lowering agents. Int J Integrative Med. 2000;2(3):9-13.

Wolerton: Comprehensive Dermatalogic Drug Therapy. 2nd ed. Philadelphia, PA: Elsevier Saunders; 2007.

Zhang XM, Jing YP, Jia MY, Zhang L. Negative transcriptional regulation of inflammatory genes by group B3 vitamin nicotinamide. Mol Biol Rep. 2012;39(12):1036-1071.

Zhao H, Yang X, Zhou R, Yang Y. Study on vitamin B1, vitamin B2 retention factors in vegetables. Wei Sheng Yan Jiu. 2008;37(1):92-96.

Review Date: 8/6/2015
Reviewed By: Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only — they do not constitute endorsements of those other sites. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Benefits of Niacin & Niacinamide

Using Niacin and Niacinamide to Boost NAD+

The main role of vitamin B3 is to make NAD molecules. This is important because the NAD molecule sits at the crossroads of mitochondrial energy production (i.e., ATP), cellular repair and signaling, and cellular defenses. Unfortunately, NAD+ levels decrease with age. This is the bad news. The good news is that there are strategies that can be used to make more NAD+. One of these is vitamin B3.

When the Food and Nutrition Board at the National Academies of Sciences, Engineering, and Medicine came up with the recommended dietary allowance (RDA) for vitamin B3, they expressed the amount recommended in NE, which stands for niacin equivalents. As an example, the RDA for adult males is 16 mg NE; it’s 14 mg NE for adult females. But for vitamin B1 (thiamine) and B2 (riboflavin), they only list the number of mg and don’t list either thiamine equivalents or riboflavin equivalents. Why the difference?

The main reason is that NAD is an example of a complex systems science principle called redundancy, which essentially means having back up plans. This molecule is so important, there’s three different ways to create it. It can be built from scratch starting from the amino acid L-tryptophan using de novo synthesis. It can be made from niacin in the Preiss-Handler pathway. And it can be produced from nicotinamide, also called niacinamide, in a salvage pathway. In Eternus we opted to use all three. In the rest of this post, we want to share a bit more about why we chose to use both niacin and niacinamide, and how we selected the doses.

Niacin is also called nicotinic acid, which gives its name (NIcotinic ACid + vitamIN). It was the 3rd of the B-complex family of vitamins discovered, hence its designation as vitamin B3. It’s been known for more than eighty years that niacin can be used to correct vitamin B3 deficiency disease (i.e., pellagra) and for more than 50 years how niacin is converted into NAD+.

Both newer and older research has indicated that niacin boosts NAD+ levels in the liver extremely quickly. Niacin might also be the preferred form of vitamin B3 for boosting NAD+ in the gut. So, the decision to include niacin in a formulation designed to support NAD+ was easy. But because niacin is the “flushing” form of vitamin B3, we wanted to include it at a dose where flushing has not been reported to occur.

Most people will experience flushing if doses of 500 mg of niacin are taken. As many as half of people flush if they take 100 mg. So we needed to go with a lower dose than this to avoid flushing. When we reviewed the extensive niacin research, the lowest dose that had been reported to cause mild flushing was 30 mg. We selected a dose to be just below this threshold to gain the additive NAD+ boosting benefits of niacin (it’s complimentary with other ways to build the NAD+ molecule), while minimizing risk of even mild flushing.

But we wanted to give more niacin equivalent activity than this lower dose of niacin alone would allow. This is where niacinamide comes into the picture. Niacinamide is also called vitamin B3. Similar to niacin, it prevents pellagra. And also similar to niacin, both older and newer research has found it can be used to make NAD+. In fact, it appears to be the preferred substrate to make NAD+ in most tissues throughout the body.

Unlike niacin, niacinamide does not cause flushing, but this doesn’t mean taking very high doses is better. At Neurohacker Collective we are interested in how living systems adapt over time. In general, adaptation occurs more quickly at higher doses. It almost seems like when we push too hard, the body pushes back harder as well, with compensatory mechanisms kicking in faster and stronger.

In the case of vitamin B3, one of the compensatory mechanisms, if we give too much vitamin B3, is an increase in demands on methylation, which is used to eliminate excess amounts. When we chose the dose of niacinamide, our goal was to use a more moderate dose: one that is high enough to work additively with niacin (and L-tryptophan) to boost NAD+, but not so high that it puts too much stress on methylation capacities.

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What are the risks of taking niacin?

  • Side effects. Niacin can cause flushing, especially when you first begin taking it. Your health care provider will probably suggest increasing the dose slowly to reduce this problem. He or she might also offer a time-release prescription formulation to control flushing. Niacin can cause upset stomach and diarrhea. However, all of these side effects tend to fade over time.
  • Risks. Niacin does have risks. It can cause liver problems, stomach ulcers, changes to glucose levels, muscle damage, low blood pressure, heart rhythm changes, and other issues. People with any health condition including liver or kidney disease, diabetes, high blood pressure, or cardiovascular problems need to talk to a doctor before using niacin supplements. Do not treat high cholesterol on your own with over-the-counter niacin supplements.
  • Interactions. If you take any medicines or supplements regularly, talk to your doctor before you start using niacin supplements. They could interact with medicines like diabetes drugs, blood thinners, anticonvulsants, blood pressure medicines, thyroid hormones, and antibiotics as well as supplements like ginkgo biloba and some antioxidants. Alcohol might increase the risk of liver problems. Though niacin is often used along with statins for high cholesterol, this combination may increase the risk for side effects. Get advice from your health care provider.

At the low DRI doses, niacin is safe for everyone. However, at the higher amounts used to treat medical conditions, it can have risks. For that reason, children and women who are pregnant or breastfeeding should not take niacin supplements in excess of the DRI unless it’s recommended by a doctor.

People with uncontrolled gout should also not take niacin supplements.

Vitamin B3, also called niacin, is one of the eight B-complex water-soluble vitamins. Niacin has a wide range of uses in the body, helping functions in the digestive system, skin and nervous system. Niacin, a name coined from nicotinic acid vitamin, comes in several forms, including niacinamide (nicotinamide) and inositol hexanicotinate. Each of these forms has various uses as well.

Food sources of niacin include yeast, meat, fish, milk, eggs, nuts, green vegetables, beans and enriched breads and cereals. The human body can also make niacin from the amino acid tryptophan, according to the National Institutes of Health (NIH).

Benefits

Like other B vitamins, niacin helps the body break down carbohydrates, fats and proteins into energy, according to the University of Maryland Medical Center. In addition, it plays a role in gland and liver function. “Niacin has a role in producing certain hormones in the adrenal glands and helps remove harmful chemicals from the liver,” Dr. Sherry Ross, women’s health expert at Providence Saint John’s Health Center in Santa Monica, California, told Live Science.

Niacin also can play a part in improving health. According to NIH, it is also used for treating migraine headaches, circulation problems and dizziness, and to reduce the diarrhea associated with cholera.

Some studies have found the taking niacin may help stroke patients. When rats with ischemic stroke were given niacin, their brains grew new blood vessels, according to researchers at Henry Ford Hospital in Detroit, Michigan. Ischemic stroke is caused by an obstruction within a blood vessel supplying blood to the brain and accounts for 87 percent of all cases. A 2000 study published in the journal Stroke also used rats and found that treatment with nicotinamide may repair damage to the brain caused by strokes.

Vitamin B3 may also be helpful to cancer patients. A recent study found that nicotinamide significantly reduces the incidence of nonmelanoma skin cancers in those with a history of basal cell carcinoma or squamous cell carcinoma.

It may be good for other skin conditions, too. In a double-blind trial by the State University of New York, the topical application of a 4 percent niacinamide gel twice a day for two months resulted in a similar acne improvement when compared to 1 percent clindamycin gel.

Those who have intimacy problems may also benefit from niacin. According to a study published in the Journal of Sexual Medicine, vitamin B3 was found to improve the ability to maintain an erection in men with moderate to severe erectile dysfunction.

A recent animal study suggested that niacin may be helpful in preventing inflammatory bowel disease and colitis. The 2017 study, published in Scientific Reports, found that rats that were given niacin and then induced with colitis saw less colonic damage than those who did not receive niacin. The authors attribute this protection to niacin’s anti-inflammatory and anti-angiogenic effects. (Angiogenic means the formation and development of blood vessels.)

Niacin and cholesterol

Niacin is known for lowering LDL (bad) cholesterol and triglycerides in the blood. Additionally, the Mayo Clinic reported that niacin could raise HDL (good) cholesterol by more than 30 percent. Therefore, niacin has been a major part of treating high cholesterol for at least 50 years. But a large-scale 2014 study has caused some health professionals to revisit that view.

The study, published in The New England Journal of Medicine, examined 50- to 80-year-olds with cardiovascular disease. They were already taking statin medication, which was combined with extended-release niacin and laropiprant, which reduces face flushing associated with niacin, for four years. Niacin did not result in the hypothesized reduced heart attacks and strokes. It also was associated with a higher risk of death from all causes and serious side effects, including liver problems, excess bleeding, infections, loss of blood sugar control in diabetics, gout and the development of diabetes. The authors of the study conclude that doctors should take these adverse effects into consideration when prescribing niacin and perhaps niacin should only be used to treat severe patients.

A 2017 article in the Journal of Clinical-Lipidology, however, cited previous studies that saw reductions in cardiovascular events in patients that combined niacin with statins. The authors of the article state that more research is needed before niacin ends its term as a cholesterol therapy mainstay.

Niacin flush

One side effect of taking niacin supplements is mild flushing. Ross described it as a feeling of warmth, itching, redness or a tingly feeling under the skin. The flushing is harmless and usually subsides within one or two hours, according to the British Columbia Drug and Poison Information Center (DPIC). Some over-the-counter niacin tablets deliver the dose in a short burst, which makes the reaction more intense. Timed-release tablets deliver the vitamin more slowly, which reduces the intensity of the flushing. However, this type of niacin may cause liver damage in some people, according to the DPIC.

Other side effects can include stomach upset, intestinal gas, dizziness and pain in the mouth, the NIH reported.

Deficiency and dosage

In the United States and other developed countries, niacin deficiency is rare and is typically found in alcoholics. According to the University of Maryland Medical Center, symptoms of mild niacin deficiency include fatigue, canker sores, vomiting, depression, poor circulation and indigestion. More severe niacin deficiency can cause a condition called pellagra. The symptoms of pellagra include digestive problems, inflamed or flakey skin, diarrhea and mental impairment.

The normal recommended daily allowance (RDA) of niacin is dependent on age, gender, health conditions and reproductive status. For women and men, the average RDA is 14 to 16 milligrams a day, according to the NIH. Those taking medications or those that have medical conditions should contact a medical professional before taking niacin due to drug interactions and side effects.

Getting too much niacin is possible, even for healthy individuals. “When taking it, you need to check for interactions with other meds and make sure your labs tests are normal,” said Dr. Kristine Arthur, internist at Orange Coast Memorial Medical Center in Fountain Valley, California. “If you take too much you can have side effects including nausea, stomach upset, abnormal liver tests, muscle breakdown and flushing — usually with over 1 to 2 grams per day.”

Many doctors advise against self-medicating with niacin and suggest that in many cases supplementation isn’t needed. “The water soluble vitamins, such as C and B complex, are much harder to reach toxic levels from over-ingestion, but does this mean we need to procure them from a supplement regularly? In most cases, the answer is no,” said Dr. David Greuner, director and co-founder of NYC Surgical Associates. Most people are able to get plenty of niacin through a healthy diet.

Additional reporting by Jessie Szalay, Live Science contributor.

Additional resources

  • University of Maryland Medical Center: Possible Interactions with Vitamin B3 (Niacin)
  • Mayo Clinic: Evidence of Effective Niacin (vitamin B3, nicotinic acid) and Niacinamide Use
  • University of Michigan: B3

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