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Niacin (By mouth)

Niacin (NYE-a-sin)

Treats high cholesterol and triglyceride levels and niacin deficiency. Also reduces heart attack risk and slows narrowing of the arteries.

Brand Name(s):

Nature's Blend Niacin, Niacor, Niaspan, PharmAssure Niacin, Slo-Niacin

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use it if you had an allergic reaction to niacin.

How to Use This Medicine:

Capsule, Long Acting Capsule, Liquid, Tablet, Long Acting Tablet

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
  • Take this medicine at bedtime with a low-fat snack. This will help decrease stomach upset.
  • Follow the instructions on the medicine label if you are using this medicine without a prescription.
  • Measure the oral liquid medicine with a marked measuring spoon, oral syringe, or medicine cup.
  • Extended-release tablet or capsule: Swallow whole. Do not crush, break, or chew it.
  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
  • Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some foods and medicines can affect how niacin works. Tell your doctor if you are using any of the following:
    • Blood pressure medicine
    • Blood thinner (including warfarin)
    • Statin medicine
    • Vitamins or other supplements that contain niacin
  • If you are also using cholestyramine, colesevelam, or colestipol, take niacin at least 4 to 6 hours after you take these medicines.
  • Avoid hot drinks, alcohol, and spicy foods around the time that you take niacin. This will decrease flushing.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have liver disease, kidney disease, diabetes, gout, heart disease, angina, low blood pressure, thyroid problems, bleeding problems, or stomach ulcers.
  • This medicine may cause the following problems:
    • Liver problems
    • Rhabdomyolysis (serious muscle problem when used with statin medicine)
    • High blood sugar levels
  • This medicine may make you dizzy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you. Stand or sit up slowly.
  • If you need to stop taking extended-release niacin, even for a short time, talk to your doctor before you start taking it again. You may need to start back on a lower dose.
  • Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
  • Muscle pain, tenderness, or weakness
  • Unusual bleeding or bruising

If you notice these less serious side effects, talk with your doctor:

  • Mild nausea or vomiting, diarrhea
  • Warmth or redness in your face, neck, arms, or upper chest

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 5/1/2020

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