5-20+ grams of adrenal-boosting vitamin C. Vitamin C (ascorbate) performs several critical functions in the body. Vitamin C is essential for life and it is the most important nutrient for your adrenal glands. Vitamin C (ascorbic acid) is commonly offered as a GMO corn-based form containing preservatives such as antifreeze. Dr Pure IV only provides the purest, non-GMO vitamin C.