R-Lipoic Acid by Natural Factors $30.99 60 Vegetarian Capsules - $30.99 Size 60 Vegetarian Capsules 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart R-Lipoic Acid is an antioxidant for the maintenance of good health.* This form of alpha-lipoic acid is a highly stable form with enhanced bioavailability.