The uses of Nicotinic acid include: Niacin (nicotinic acid) is used to prevent and treat niacin deficiency (pellagra). Niacin deficiency may result from certain medical conditions (e.g., alcohol abuse, malabsorption syndrome, Hartnup disease), poor diet, or long-term use of certain medications (e.g., isoniazid).
Niacin deficiency can cause diarrhea, confusion (dementia), tongue redness/swelling, and peeling red skin. Niacin is also known as vitamin B3 , one of the B-complex vitamins. Vitamins help to support the body's ability to make and break down natural compounds (metabolism) needed for good health.