ORIGINAL SCIENTIFIC REPORT
Topical Minoxidil Versus Topical Diltiazem for Chemical
Sphincterotomy of Chronic Anal Fissure: A Prospective,
Randomized, Double-Blind, Clinical Trial
Published online: 31 December 2017
Internationale de Chirurgie 2017
Background Anal ﬁssure is a common anorectal problem causing severe pain and discomfort to the patients.
Chemical sphincterotomy has emerged as a noninvasive alternative to the surgical methods of ﬁssure treatment. The
objective of this study was evaluation of the efﬁcacy and the adverse effects of topically applied minoxidil in
chemical sphincterotomy of chronic anal ﬁssure in comparison with topical diltiazem.
Methods A total of 88 patients with chronic anal ﬁssure aged between 15 and 65 years were included in this double-
blind, randomized clinical trial and were randomly assigned to either 0.5% minoxidil cream or 2% diltiazem cream
twice daily for 2 weeks. The pain intensity, bleeding, wound healing, itching, headache, dizziness, signiﬁcant drop in
blood pressure, allergy and ﬁssure relapse were assessed on a monthly basis for 2 months.
Results Both diltiazem and minoxidil reduced the pain, bleeding and improved ﬁssure healing with no signiﬁcant
difference. There were no between-groups differences in the frequencies of adverse effects, except for itching which
was slightly higher with minoxidil during the ﬁrst month. Allergy occurred in two patients in the minoxidil group,
which was not severe and did not lead to discontinuation of the trial.
Conclusion Topically administered minoxidil is of equal efﬁcacy as diltiazem in the treatment of chronic anal ﬁssure
with low frequency of adverse effects. Thus, it can be considered as an agent for chemical sphincterotomy of anal
ﬁssure, but the itching at the beginning of the treatment can affect the adherence of the patient to treatment.
Trial registration number IRCT2015041414483N6 (the full trial protocol could be accessed online at www.irct.ir).
Anal ﬁssure is linear, longitudinal tear or split in the
epithelial lining of the distal anal canal which is one of the
most common anorectal problems [1–4]. It is generally
deﬁned as ‘‘A linear ulcer of the anoderm, distal to the
dentate line, generally located in the posterior midline’’ .
Anal ﬁssure is often associated with severe sharp pain upon
defecation, described as ‘‘tearing’’  or ‘‘passing broken
glass’’  and bleeding, followed by a less severe burning
pain which may last for several hours afterward [2–6].
Other less common symptoms include pruritus, swelling,
prolapse, anal discharge, constipation, dyspareunia and
dysuria [3, 4].
& Shahram Ala
Department of Surgery, Faculty of Medicine, Mazandaran
University of Medical Sciences, Sari, Mazandaran Province,
Department of Clinical Pharmacy, Faculty of Pharmacy,
Mazandaran University of Medical Sciences, 18th Km
Farahabad Boulevard, Sari, Mazandaran Province 48175861,
Department of Health, Biostatistics and Medical Research,
Mazandaran University of Medical Sciences, Sari,
Mazandaran Province, Iran
World J Surg (2018) 42:2252–2258