Niacin Interactions

Niacin can have possible interaction with other medications or drugs you may be taking. If you are currently taking any of the following, you should talk with your doctor before taking Niacin.

Blood thinners
Niacin can potentially increase the effect of these medications, increasing the risk of bleeding.

Alpha blockers and blood pressure medications
Niacin can increase the effectiveness of medications taken to lower blood pressure.

Statins 
Some studies indicate taking niacin with simvastatin (Zocor) appears to slow down the progression of heart disease. However, the combination may also increase the likelihood for serious side effects, such as muscle inflammation or liver damage. If you are taking a statin, consult with your doctor before taking any Niacin supplement.


Cholesterol-lowering medications 
Niacin binds the cholesterol lowering medications known as bile-acid sequestrants and may make them less effective. Bile-acid sequestrants include colestipol (Colestid), colesevelam (Welchol), and cholestyramine (Questran). Take niacin and these medications at different times of the day (not together).

Tetracycline 
Don't take Niacin at teh same time as the antibiotic tetracycline, Niacin can interfere with absorption and effectiveness. All vitamin B complex supplements should be taken at different times from tetracycline.  Niacin in the morning, tetracycline in the evening for example.

Anti-seizure medications
Phenytoin (Dilantin) and valproic acid (Depakote) have been associated with Niacin deficiency in some people. Taking Niacin with carbamazepine (Tegretol) or mysoline (Primidone) may increase levels of these medications in the body.
  Diabetes medications
Niacin has the potential to increase blood sugar levels. People taking medications used to treat high blood glucose levels should closely monitor blood sugar levels when taking Niacin.

Nicotine patches 
Using nicotine patches while taking Niacin can increase the potential of experiencing a Niacin flush.


Isoniazid (INH)
INH is a medicine used to treat tuberculosis and can cause Niacin deficiency.

Some medications can lower Niacin levels:

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

 If you're taking one of these medication, discus the need for a Niacin supplement with your doctor.