Niacinamide (nicotinamide) is a form of vitamin B3 (niacin) and is used to prevent and treat niacin deficiency (pellagra). Niacin deficiency can cause diarrhea, confusion (dementia), tongue redness/swelling, and peeling red skin. Niacinamide is often used instead of niacin because it causes fewer side effects (e.g., flushing). Unlike niacin, niacinamide does not help correct blood fat levels and cannot be substituted for niacin if you are being treated for a blood fat problem (e.g., high cholesterol).
Niacin deficiency may happen as a result of poor diet, certain medical conditions (e.g., alcohol abuse, malabsorption syndrome, Hartnup disease), or long-term use of certain medications (e.g., isoniazid). It is best to get your vitamins from healthy foods. A multivitamin may be recommended by your doctor instead of niacinamide because poor diet usually causes deficiencies in more than one vitamin. Vitamins help to support the body's ability to make and break down natural substances (metabolism) and are needed for good health.
Take this product by mouth as directed, usually once or twice daily. Follow all directions on the product package, or use as directed by your doctor. If you are uncertain about any of the information, consult your doctor or pharmacist.
Do not crush or chew extended-release tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split the tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing.
If you take certain drugs to lower blood fats (bile acid-binding resins such as cholestyramine or colestipol), take niacinamide at least 4 to 6 hours before or after taking these medications. These products may bind with niacinamide, preventing its full absorption.
If your condition persists or worsens, or if you think you may have a serious medical problem, seek immediate medical attention.
If your doctor has directed you to use this medication, remember that he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if any of these rare but very serious side effects occur: black/tarry stools, easy bruising/bleeding, persistent nausea/vomiting, swelling of arms/legs, change in the amount of urine, dark urine, vomit that looks like coffee grounds, yellowing eyes/skin.
A very serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction may include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Before taking niacinamide, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This product should not be used if you have certain medical conditions. Before using this product, consult your doctor or pharmacist if you have: current liver disease, current ulcer.
If you have any of the following health problems, consult your doctor or pharmacist before using this product: bleeding problems (low platelets), diabetes, gout, kidney disease, history of liver disease, history of stomach/ulcer problems.
If you have diabetes, this drug may increase your blood sugar levels. Check your blood glucose levels regularly as directed by your doctor. Tell your doctor immediately if you have symptoms of high blood sugar such as increased thirst and urination. Your anti-diabetic medication or diet may need to be adjusted.
Tell your doctor if you are pregnant before using this medication.
If you are taking this medication under your doctor's direction, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.
Before using this product, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: blood thinners (e.g., warfarin, heparins), vitamins/dietary supplements/products that also contain niacin or niacinamide.
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
Laboratory tests (e.g., blood sugar, liver function tests) may be performed to monitor for possible side effects.
Keep all regular medical and laboratory appointments.
Remember that it is best to get your vitamins and minerals from healthy foods. Maintain a well-balanced diet, and follow any dietary guidelines as directed by your doctor. B vitamins (including niacin) are found in meat, fish, poultry, enriched/whole grain bread products, and fortified cereals. Eat more of these foods to increase the amount of niacin in your diet if you have a niacin deficiency.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Refer to storage information printed on the package. If you have any questions about storage, ask your pharmacist. Keep all products away from children and pets.
Information last revised March 2013. Copyright(c) 2013 First Databank, Inc.
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