In the U.S.—

In Canada—

Other commonly used names are nicotinic acid; vitamin B₃.

• Antihyperlipidemic

Niacin (NYE-a-sin) is used to help lower high cholesterol and fat levels in the blood. This may help prevent medical problems caused by cholesterol and fat clogging the blood vessels.

Some strengths of niacin are available only with your doctor's prescription. Others are available without a prescription, since niacin is also a vitamin. However, it is best to take it only under your doctor's direction so that you can be sure you are taking the correct dose.

Niacin for use in the treatment of high cholesterol is available in the following dosage forms:

Oral
• Extended-release capsules (U.S.)
• Solution (U.S.)
• Tablets (U.S. and Canada)
• Extended-release tablets (U.S. and Canada)

If you are taking this medicine without a prescription, carefully read and follow any precautions on the label. For niacin, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to niacin. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Diet—Before prescribing medicine for your condition, your doctor will probably try to control your condition by prescribing a personal diet for you. Such a diet may be low in fats, sugars, and/or cholesterol. Many people are able to control their condition by carefully following their doctor's orders for proper diet and exercise. Medicine is prescribed only when additional help is needed and is effective only when a schedule of diet and exercise is properly followed.

Also, this medicine is less effective if you are greatly overweight. It may be very important for you to go on a reducing diet. However, check with your doctor before going on any diet.

Make certain your health care professional knows if you are on any special diet, such as a low-sodium or low-sugar diet.

Pregnancy—Studies have not been done in either humans or animals.

Before taking niacin, make sure your doctor knows if you are pregnant or if you may become pregnant. It may be necessary for you to stop taking this medicine or to take another medicine while you are pregnant. Be sure you have discussed the risks and benefits of the medicine with your doctor.

Breast-feeding—Niacin passes into human breast milk and may cause unwanted effects in nursing babies. It may be necessary for you to take another medicine or to stop breast-feeding during treatment. Be sure you have discussed the risks and benefits of the medicine with your doctor.

Children—There is no specific information comparing the use of niacin for high cholesterol in children with use in other age groups. However, use is not recommended in children under 2 years of age since cholesterol is needed for normal development.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. Although there is no specific information comparing the use of niacin for high cholesterol in the elderly with use in other age groups, it is not expected to cause different side effects or problems in older people than in younger adults.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are using any other prescription or nonprescription (over-the-counter [OTC]) medicine.

• Adrenergic Blocking agents (medicine for the heart) or
• Alcohol or
• Anticoagulants (medicine to keep your blood thin) or
• Antihypertensives (medicine for high blood pressure) or
• Bile Acid Sequestrants (medicine used to treat high cholesterol) or
• Calcium channel blockers (medicine for heart problems or high blood pressure) or
• HMG-CoA reductase inhibitors (medicine to lower your cholesterol) or
• Nitrates (e.g., nitroglycerin and isosorbide)—Niacin may increase the effects of these medications or may have increased side effects when these drugs are given together.

• Bleeding problems or
• Diabetes mellitus (sugar diabetes) or
• Glaucoma or
• Gout or
• Liver disease or history of jaundice
• Low blood pressure or
• Stomach ulcer—Niacin may make these conditions worse

• Kidney problems—Niacin (extended release tablets) may make your kidney problems worse.

Use this medicine only as directed by your doctor. Do not use more or less of it, do not use it more often, and do not use it for a longer time than your doctor ordered. To do so may increase the chance of unwanted effects.

Remember that niacin will not cure your condition but it does help control it. Therefore, you must continue to take it as directed if you expect to keep your cholesterol levels down.

Follow carefully the special diet your doctor gave you. This is the most important part of controlling your condition, and is necessary if the medicine is to work properly.

If this medicine upsets your stomach, it may be taken with meals or milk. If stomach upset (nausea or diarrhea) continues, check with your doctor.

For patients taking the extended-release capsule form of this medicine:

• Swallow the capsule whole. Do not crush, break, or chew before swallowing. However, if the capsule is too large to swallow, you may mix the contents of the capsule with jam or jelly and swallow without chewing.

For patients taking the extended-release tablet form of this medicine:

• Swallow the tablet whole. If the tablet is scored, it may be broken, but not crushed or chewed, before being swallowed.
• Tablet (Niaspan) should be taken at bedtime after a low-fat snack.
• To decrease flushing of your face (redness), take aspirin or ibuprofen (e.g., Advil, Motrin) 30 minutes before taking tablet (Niaspan).
• Avoid drinking alcohol or hot drinks around the time you take your tablet (Niaspan). This helps decrease flushing of your face (redness).
• Take this medication exactly as your doctor ordered. If you stop taking this medication for any period of time, contact your doctor prior to restarting taking niacin.

Dosing—

The dose of niacin will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of niacin. If your dose is different, do not change it unless your doctor tells you to do so.

The number of capsules or tablets or teaspoonfuls of solution that you take depends on the strength of the medicine.

• For oral dosage form (extended-release capsules, extended-release tablets, oral solution, or regular tablets):
  • For treatment of high cholesterol:
    • Adults and teenagers—500 milligrams to 2 grams one to three times a day: use and dose will be determined by your doctor. Do not exceed the amount the doctor prescribes.
    • Children—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Store extended release tablets (Niaspan) at room temperature.
• Keep the liquid form of this medicine from freezing.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly to lower your cholesterol and triglyceride (fat) levels and if you should continue to take it.

Do not stop taking niacin without first checking with your doctor. When you stop taking this medicine, your blood cholesterol levels may increase again. Your doctor may want you to follow a special diet to help prevent this from happening.

Do not take vitamins or other dietary supplements unless they have been discussed with your doctor. This especially includes vitamins or dietary supplements that contain niacin or similar ingredients.

This medicine may affect blood sugar levels. If you notice a change in the results of your blood or urine sugar tests or if you have any questions, check with your doctor.

This medicine may cause you to feel dizzy or faint, especially when you get up from a lying or sitting position. Getting up slowly may help. This effect should lessen after a week or two as your body gets used to the medicine. However, if the problem continues or gets worse, check with your doctor.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Check with your doctor immediately if any of the following side effects occur:

• Less common
  • With prolonged use of extended-release niacin
    • Darkening of urine;  light gray-colored stools;  loss of appetite;  severe stomach pain;  yellow eyes or skin 
    
    

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• Less common
  • Abdominal pain;  feeling of warmth;  flushing or redness of skin, especially on face and neck;  headache;  rash;  runny nose;  sneezing;  stuffy nose 
  
  

• With high doses
  • Diarrhea;  dizziness or faintness;  dryness of skin;  fever;  frequent urination;  itching of skin ;  joint pain;  muscle aching or cramping;  nausea or vomiting;  side, lower back, or stomach pain;  swelling of feet or lower legs;  unusual thirst;  unusual tiredness or weakness;  unusually fast, slow, or irregular heartbeat 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your health care professional.