We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What are the Most Common Niacin Reactions?

By Colette Larson
Updated May 17, 2024
Our promise to you
WiseGeek is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WiseGeek, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Niacin, also referred to as vitamin B3 and nicotinic acid, is a water-soluble vitamin found in a variety of foods, including fish, chicken, beef, cereal and peanuts. Considered one of the body's essential nutrients, the recommended daily allowance of niacin is 14 milligrams per day for women, 16 milligrams per day for men, 2-12 milligrams per day for children and 18 milligrams per day for women who are breast-feeding or pregnant. Ingesting much more than the recommended amount can lead to niacin reactions that might include a variety of dermatological conditions such as facial flushing, dry skin, itching and skin rashes. Gastrointestinal complaints, such as indigestion, and liver toxicity are other common niacin reactions. All nutritional supplements or medications can cause allergic reactions, but most people experience limited or no adverse side effects as a result of consuming niacin within its recommended daily allowance.

The most common and noticeable of the niacin reactions is blood vessel dilation, which might be exhibited as facial flushing. Flushing usually begins within five to 10 minutes after ingesting a niacin dose above 75 milligrams and might last as long as 20-30 minutes. During a niacin flush, the affected individual's face grows hot and takes on a bright red tone. The flushing might spread throughout the upper body and might occasionally be accompanied by itching, tingling or rashes. Other niacin reactions related to flushing are dizziness, fainting, chills, shortness of breath, sweating or an elevated heart rate.

Even in therapeutic doses, gastrointestinal issues are among the more common niacin reactions. These include stomach pain, heartburn, indigestion, nausea, vomiting, diarrhea and flatulence. To avoid gastrointestinal issues, take niacin either with food or immediately following a meal. Gastrointestinal difficulties also might be avoided by beginning a niacin therapy program at a lower dosage and gradually building up to a higher dosage over a period of several weeks.

Individuals taking niacin at doses exceeding 2 grams per day are at risk of developing niacin-related liver toxicity. Extended-release niacin preparations are more likely to cause niacin reactions than the immediate release preparations. Liver toxicity is exhibited by jaundice, inflammation of the liver and elevated liver enzymes. Liver enzymes of individuals who have been prescribed long-term niacin therapy are typically monitored regularly to screen for possible liver damage.

WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.