The average Niacinamide cash price is about $9.24 for a supply of: Tablet 500 MG 30 pcs. Get our free Niacinamide coupon and be eligible to receive a discount. You can reduce your Niacinamide cost by up to 75% with our free Niacinamide discount card. Bring it to a participating pharmacy near you to save on your prescription medication.Treating or preventing low levels of niacin (vitamin B3). It may also be used for other conditions as determined by your doctor. Niacinamide is a vitamin B supplement. It works by replacing vitamin B3 in the body.