Extravasation of toxic chemotherapeutic 'agents cause severe skin ulceration and necrosis which often need secondary surgical intervention. Still, there were not established antidote agent in case of extravasation with mitomycin-c. Dimethyl sulfoxide is known as an effective chemical scavenger of toxic hydroxyl free radical and sodium thiosulfate also was demonstrated significant protector from mitomycin-c induced ulceration by a few experimental studies. Author investigated necrotic area of mitomycin-c injected site and compare to the effectiveness of topical treatment with dimethyl sulfoxide and intradermal injection of sodium thiosulfate according to starting times, forty five mice were divided into 3 groups. Control group(n=5) had no treatment after subcutaneous injection of mitomycin-c. Experimental group I and 11 were 20 mice treated dimethyl sulfoxide and sodium.