Niacin 100 mg plus B3 Tablets, 60 ct, QC90327 Sale! This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. Niacin (Vitamin B-3) can play a role in energy metabolism. Helps convert food into energy and supports skin, digestive and nervous system health. No added sugar, yeast, preservatives, artificial flavors, or colors, and gluten-free.