What is the recommended treatment for an anal fissure?

Treatment of Anal Fissure

Start with conservative management including increased fiber intake and adequate water consumption, and if this fails after 2 weeks, add topical calcium channel blockers (0.3% nifedipine with 1.5% lidocaine) applied three times daily for at least 6 weeks, which achieves 95% healing rates. 1

Initial Conservative Management (First 2 Weeks)

• Increase dietary fiber through food or supplements to soften stools, which heals approximately 50% of acute anal fissures within 10-14 days 1
• Ensure adequate water intake to prevent constipation and promote healing 1
• Warm sitz baths promote sphincter relaxation and should be used regularly 1
• Topical lidocaine can be applied for pain control as needed 1

Pharmacological Treatment (If No Improvement After 2 Weeks)

The preferred agent is topical calcium channel blockers, specifically 0.3% nifedipine combined with 1.5% lidocaine, applied three times daily for at least 6 weeks 1. This combination achieves 95% healing rates by blocking calcium channels in vascular smooth muscle, reducing internal anal sphincter tone and increasing blood flow to the ischemic ulcer 1.

• Pain relief typically occurs after 14 days of treatment with topical calcium channel blockers 1
• Continue treatment for the full 6-week course even if symptoms improve earlier 1
• Calcium channel blockers are cost-effective compared to surgical interventions 1

Alternative Pharmacological Options

While glyceryl trinitrate (nitroglycerin) ointment is sometimes used, it has lower healing rates (25-50%) and causes headaches in up to 77% of patients 1, 2. Research shows high recurrence rates (67% at 9 months) with nitroglycerin for chronic fissures 2, and some studies found no benefit over placebo 3.

Surgical Intervention (After 8 Weeks of Failed Conservative Management)

Reserve surgery only for fissures that don't respond after 8 weeks of comprehensive non-operative management 1. Lateral internal sphincterotomy is the gold standard surgical procedure, achieving healing in over 95% of cases with recurrence rates of only 1-3% 1, 4.

• Never perform surgery for acute fissures 1
• Surgery is far more effective than any medical therapy for chronic fissures 5
• The risk of permanent incontinence exists but is controversial in the literature 4, 6

Critical Pitfalls to Avoid

• Never perform manual dilatation due to high risk of permanent incontinence 1, 6
• Do not rush to surgery for acute fissures; always attempt non-operative management first 1
• Evaluate atypical features urgently: lateral location, multiple fissures, or failure to heal require workup for Crohn's disease, inflammatory bowel disease, HIV/AIDS, tuberculosis, syphilis, or malignancy 1, 7

Red Flags Requiring Urgent Evaluation

Lateral anal fissures are atypical (90% of typical fissures occur in the posterior midline) and mandate urgent evaluation for serious underlying conditions before initiating any treatment 7:

• Crohn's disease (most common cause of atypical fissures) 7
• HIV/AIDS and associated infections 7
• Ulcerative colitis 7
• Tuberculosis and syphilis 7
• Malignancy including leukemia and anal cancer 7

Pediatric Considerations

The treatment algorithm is similar for children, with conservative management as first-line therapy 8:

• Age-appropriate fiber intake and adequate fluids 8
• Stool softeners if dietary changes are insufficient 8
• Warm sitz baths and topical lidocaine for pain control 8
• Most acute fissures in children heal within 10-14 days with conservative management 8
• If persistent beyond 2 weeks, consider topical calcium channel blockers (healing rates 65-95%) 8
• Strongly avoid manual dilatation and surgery in acute pediatric fissures 8
• Surgery only for chronic fissures non-responsive after 8 weeks 8