niacin (nicotinic acid)

Do not take this medication if you are allergic to niacin, or 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 niacin. 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 niacin.

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.

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. Niacin is also present in many multiple vitamins and nutritional supplements.

Niacin is used to treat and prevent a lack of natural niacin in the body, and to lower cholesterol and triglycerides (types of fat) in the blood. It is also used to lower the risk of heart attack in people with high cholesterol who have already had a heart attack. Niacin is sometimes used to treat coronary artery disease (also called atherosclerosis).

Niacin may also be used for purposes other than those listed in this medication guide.

Do not take this medication if you are allergic to niacin, or if you have severe liver disease, a stomach ulcer, or active bleeding.

Before taking niacin, tell your doctor if you are allergic to any drugs, or if you have:

• liver or kidney disease;
• heart disease or uncontrolled angina (chest pain);
• a stomach ulcer;
• diabetes;
• gout; or
• a muscle disorder such as myasthenia gravis.

If you have any of these conditions, you may not be able to use niacin, or you may need dosage adjustments or special tests during treatment.

FDA pregnancy category C. Niacin may be harmful to an unborn baby when the medication is taken at doses to treat high cholesterol or other conditions. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Niacin can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

Niacin is sometimes taken at bedtime with a low-fat snack. Follow your doctor's instructions.

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 niacin. These effects should disappear over time as you keep taking the medication.

Take niacin with a full glass of cold or cool water. Taking the medication with a hot drink may increase your risk of side effects such as flushing.

Do not crush, chew, break, or open an extended-release tablet or capsule. Swallow the pill whole. It is specially made to release medicine slowly in the body. Breaking or opening the pill would cause too much of the drug to be released at one time.

Niacin extended-release tablets and capsules contain higher strengths of the medicine than the regular niacin tablets. Take only the dose that is correct for the type of niacin tablet or capsule you are using.

Niacin can cause you to have unusual results with certain medical tests (urine tests). Tell any doctor who treats you that you are using niacin.

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.

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.

To be sure this medication is not causing harmful effects, your blood will need to be tested on a regular basis. Your kidney or liver function may also need to be tested. Do not miss any scheduled appointments.

Store niacin at room temperature away from moisture and heat.

Take the missed dose as soon as you remember. Be sure to take the missed dose with food if you normally take your niacin dose with a meal or snack.

If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include nausea, dizziness, itching, vomiting, upset stomach, and flushing.

Avoid drinking hot beverages shortly after taking niacin. Hot drinks can worsen niacin's flushing effect (warmth, itching, redness, or tingly feeling under your skin).

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

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 niacin.

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.

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

Call your doctor at once if you have any of these serious side effects:

• feeling light-headed, fainting;
• fast, pounding, or uneven heart beats;
• feeling short of breath;
• swelling;
• jaundice (yellowing of your skin or eyes); or
• muscle pain, tenderness, or weakness with fever or flu symptoms and dark colored urine.

If you are diabetic, tell your doctor about any changes in your blood sugar levels.

Less serious side effects of niacin include:

• mild dizziness;
• warmth, redness, or tingly feeling under your skin;
• itching, dry skin;
• sweating or chills;
• nausea, diarrhea, belching, gas;
• muscle pain, leg cramps; or
• sleep problems (insomnia).

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect.

Tell your doctor about all other cholesterol-lowering drugs you are taking with niacin, especially atorvastatin (Lipitor), fluvastatin (Lescol), lovastatin (Mevacor), pravastatin (Pravachol), or simvastatin (Zocor).

Before taking niacin, tell your doctor if you are also using any of the following drugs:

• a blood thinner such as warfarin (Coumadin);
• multivitamins or mineral supplements that contain niacin;
• blood pressure or heart medications such as amlodipine (Norvasc), diltiazem (Tiazac, Cartia, Cardizem), felodipine (Plendil), nicardipine (Cardene), nifedipine (Procardia, Adalat), nimodipine (Nimotop), nisoldipine (Sular), or verapamil (Calan, Covera, Isoptin, Verelan); or
• heart medications such as doxazosin (Cardura), isosorbide (Dilatrate, Imdur, Isordil, Monoket, Sorbitrate), nitroglycerin (Nitro-Bid, Nitro-Dur, Nitrostat), prazosin (Minipress), or terazosin (Hytrin).

This list is not complete and there may be other drugs that can interact with niacin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Your pharmacist can provide more information about niacin.