Higher doses of niacin can help lower cholesterol, but long-term treatment with niacin — particularly with extended-release forms — may damage the liver.
Niacin is a water-soluble vitamin. It is an
This article examines how niacin can damage the liver. It also discusses the signs of liver damage due to too much niacin and the next steps a person should take.
Niacin — also called vitamin B3 — is a water-soluble vitamin naturally present in many foods.It is also available as two dietary supplements: nicotinic acid and nicotinamide.
A healthcare professional may prescribe nicotinic acid to help treat high cholesterol. Prescription-strength nicotinic acid can play a role in reducing low-density lipoprotein (LDL) cholesterol, or “bad” cholesterol, while increasing levels of high-density lipoprotein (HDL) cholesterol, or “good” cholesterol.
However, high doses and long-term treatment can lead to issues with the liver, such as hepatitis and liver failure. Certain high doses have associations with liver damage.
According to a
Experts theorize that high doses of niacin
Doses of 1,000–3,000 milligram (mg) per day of nicotinic acid can lead to serious adverse effects, such as:
- hypotension, or low blood pressure
- insulin resistance
- blurred and impaired vision
Additionally, Oregon State University suggests that previous research found that liver toxicity can occur at doses as little as 500–750 mg per day.
The ODS also notes that signs of liver toxicity can occur if a person takes 3,000 mg per day of nicotinamide. Although nicotinamide has fewer adverse effects than nicotinic acid, some people undergoing dialysis have been seen to experience adverse effects when taking doses of 500–1,500 mg per day.
People should only take niacin under the direct supervision of a doctor and enquire about the correct dosing.
A person should speak with a doctor if they believe they have taken too much niacin.
Signs of liver damage include:
People should only take niacin under the supervision of a doctor.
In some cases, elevated levels of niacin can lead to moderate to severe liver damage. When this occurs, it can cause liver failure, which can result in death.
Niacin can increase levels of serum aminotransferase, which indicate liver damage. It can take weeks or months for the serum enzyme elevations to resolve.
People should discuss their individual treatment plans with a doctor. A
If the niacin levels have caused severe damage, it can result in liver failure. This can be fatal or require an emergency liver transplant.
Niacin is an essential vitamin that the body needs for several functions.
The levels of niacin that a person consumes via food or drink naturally will not lead to liver damage.
However, high doses can result in liver damage, and long-term treatment can result in liver failure.
A person taking niacin to lower cholesterol levels should take the medication as a doctor prescribes. They should also inform the doctor if they notice any unusual side effects when taking niacin supplements or prescription-strength doses.