Topical Vitamin C
Vitamin C (ascorbic acid) is an important water soluble micronutrient that plays several roles in the human body. It is an antioxidant and a free radical scavenger and serves as an essential cofactor for many enzymatic reactions through iron-, copper- and 2-oxoglutarate-dependent dioxygenases. Mucosal damage after paraquat ingestion is not only due to its caustic nature but also paraquat ingestion causes an accumulation of free radicals which exacerbate inflammation causing extensive mucosal and tissue damage. Vitamin C neutralizes those free radicals generated after paraquat ingestion therefore enhancing body’s antioxidant stores in order to prevent mucosal damage and to maintain healthy oral tissues.25 45 Vitamin C also plays an important role in immunomodulation, and its deficiency results in impaired immune responses.46 Ascorbic acid plays an important part in wound healing; this is mainly attributed to its role in collagen synthesis and the hydroxylation of lysine and proline.47 48These three major roles; antioxidant, immunomodulation and wound healing, are significant in the treatment of mucosal damage induced by paraquat. Two clinical trials were highlighted. The first trial used 0.2 Vit C that was taken orally three times a day.18 The second trial inco-operated 5 grams Vit C as one of the ingredients in the formulation of a compounded paste. 25 Both trials reported positive outcomes in relation to pain reduction and oral mucositis severity.