Vitamin C, also known as Ascorbic Acid, is a vitamin found in food and used as a dietary supplement. Vitamin C is used to prevent or treat low levels of vitamin C in people who do not get enough of the vitamin from their diets. Most people who eat a normal diet do not need extra ascorbic acid. Low levels of vitamin C can result in a condition called scurvy. Ascorbic Acid may also be used for purposes not listed in this medication guide.