evaluation of topical l-arginine gel and comparison with lateral internal sphincterotomy in treatment of chronic anal fissure

background: at present, surgery is the best method for chronic anal fissure, but by acquiring more knowledge about the pathogenesis and function of internal anal sphincter, non surgical treatment such as using of glycerin trinitrate, isosorbide, bethancol, diltiazem and butilinum toxin has been suggested. there is controversy about using of l-arginine. the aim of the present study was to compare the effect of l-arginine (chemical sphincterotomy) with lateral internal sphincterotomy (surgical sphincterotomy) in treatment of chronic anal fissure. materials and methods: this clinical trial study was performed on 60 patients referring to our hospital complaining for chronic anal fissure. they were randomly divided in tow groups of equal number: patients undergoing internal sphinctrotomy (control), and using of topical l-arginine gel (case). all of the patients under study where followed for three months, data about pain, bleeding, and wound healing were recorded, and analyzed by spss 11 software, chi- square and t-test. results: the results observed in this study showed that in case group, rectal bleeding discontinued in 70% and pain controlled in 70%, while wound healing occurred in only 26.7%. in control group, 100% had no pain and no bleeding after treatment and wound healing occurred in 56.7% . conclusion: local application of l-arginine can not replace internal sphinctrotomy, but can be used when patient is unwilling for surgery and in cases with underlying disease.