List of products in the National Drug Code with proprietary name aape skin ampoule. Niacinamide (nicotinamide) is a form of vitamin B3 (niacin) and is used to prevent and treat niacin deficiency (pellagra). Niacin deficiency can cause diarrhea, confusion (dementia), tongue redness/swelling, and peeling red skin. Niacinamide is often used instead of niacin because it causes fewer side effects (e.g., flushing). Unlike niacin, niacinamide does not help correct blood fat levels and cannot be substituted for niacin if you are being treated for a blood fat problem (e.g., high cholesterol). Niacin deficiency may happen as a result of poor diet, certain medical conditions (e.g., alcohol abuse, malabsorption syndrome, Hartnup disease), or long-term use of certain medications (e.g., isoniazid). It is best to get your vitamins from healthy foods. A multivitamin may be recommended by your doctor instead of niacinamide because poor diet usually causes deficiencies in more than one vitamin. Vitamins help to support the body's ability to make and break down natural substances (metabolism) and are needed for good health.