Amazon.com: DEAL SUPPLEMENT NAC Supplement (N Acetyl Cysteine) 1,000mg Per Serving with Reduced Glutathione, 240 Capsules Antioxidant Support for Immune Health, Lung, & Liver Function : Health & Household N Acetyl L Cysteine (NAC) Superior Supplement Products Science First Designs for Health NAC is a great supplement. It's awesome stuff to support healthy lungs. NAC is a known mucolytic. That is a fancy term meaning breaking up mucus. Now, research does show that NAC L Glutathione VS NAC: Differences, Similarities, and Uses