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Updated June 09, 2015.

Question: Which Medications Can Interfere with Nicotinic Acid?

I am taking nicotinic acid to help lower my cholesterol and triglyceride levels. Are there any medications that could interact with it?

Answer:

Nicotinic acid, also known as niacin or vitamin B3, is available as an over-the-counter supplement or by prescription. This popular supplement can lower LDL cholesterol and triglyceride levels, as well as raise HDL, or “good” cholesterol, levels.

There are many formulations of nicotinic acid, including extended release and immediate release formulations.

Although nicotinic acid is considered a vitamin, that doesn’t mean that it won’t interact with other medications you are taking. Nicotinic acid can interact with certain medications, resulting in lowered effectiveness of niacin, or increased concentrations of nicotinic acid in the body, leading to increased side effects. The following medications can interact with nicotinic acid:

• Statins – All statins can interact with nicotinic acid, increasing levels of nicotinic acid in the body and raising your risk of potentially dangerous side effects, such as myopathy or rhabodmyolysis.
• Bile acid resins – All bile acid resins, including Colestid (colestipol) and Questran (cholestyramine), can lower the effectiveness of nicotinic acid.
• Zetia (ezetimibe) – Taking Zetia and nicotinic acid together may increase the concentrations of both medications in the body, increasing your risk of developing myopathy or rhabdomyolysis.

This list is not comprehensive, so you should consult with your healthcare provider, pharmacist, or medication package insert to see if any other medications will interact with nicotinic acid. Taking a combination of nicotinic acid and statins is commonly used -- can be very helpful -- in lowering LDL and in increasing HDL cholesterol. However, this combination should be only used under the supervision of your healthcare provider. If you are taking statins, do not add nicotinic acid to your cholesterol-lowering regimen without consulting your healthcare provider first. Additionally, you should consult your healthcare provider if any other medications are prescribed to you, including supplements, over-the-counter products, or other prescription drugs, in order to make sure that they will not interact with nicotinic acid.

Is There Anyway to Avoid These Interactions?

If you are taking a bile acid resin and nicotinic acid, you can avoid potential interactions by spacing the amount of time between taking the each by four to six hours. For instance, if you take your bile acid resin at 8:00 am, you may want to wait and take your nicotinic acid tablet between noon and 2:00 pm.

There may be times where your healthcare provider may prescribe another medication listed above -- in addition to nicotinic acid. When this occurs, you should be closely monitored for side effects. Always let new healthcare providers and pharmacists know that you are taking nicotinic acid in order to avoid potential drug interactions. If questions or concerns arise regarding your cholesterol-lowering therapy, or other medications prescribed, you should consult with your healthcare provider.

<sub>Sources:

Dipiro JT, Talbert RL. Pharmacotherapy: A Pathophysiological Approach, 7th ed 2008.

Micromedex Healthcare Series [intranet database]. Version 5.1. Greenwood Village,CO: Thomson Reuters (Healthcare) Inc.</sub>