Side Effects of Taking a Niacin Supplement

Niacin, which is also called nicotinic acid and vitamin B3, is a vitamin that naturally occurs in foods you may eat, such as milk, fish, meat, eggs and whole grains, and in commercially produced dietary supplements. Supplements of niacin may be taken as a way to lower your cholesterol and prevent artery disease and recurrent heart attacks, but side effects from these dietary supplements may occur. According to Drugs.com and the National Library of Medicine, side effects of taking a niacin supplement include skin changes and digestive problems.

Skin Changes

• Supplements of niacin may cause flushing or redness of your skin, especially your face and neck, although taking extended-release supplements may reduce this effect.

Dizziness

• Niacin supplements may cause you to feel dizzy or lightheaded shortly after swallowing them; taking the supplement on a full stomach may prevent this symptom.

Itching

• You may experience itching all over your body soon after taking a niacin supplement, and taking niacin for a long period of time may result in dryness and flaking of your skin.

Upset Stomach

• Digestive problems, including gas, bloating, loss of appetite, nausea, vomiting and diarrhea, are side effects of taking niacin.

Cramps

• Niacin may cause you to have cramps in your large muscles, such as those in your back, legs and upper arms.

Sleep Disorders

• If you take niacin too close to your bedtime, you may experience difficulty falling asleep or staying asleep (insomnia).