What are the management options for anal fissures?

Anal Fissure Management

Start with conservative management for all acute anal fissures, escalating to topical calcium channel blockers (specifically 0.3% nifedipine with 1.5% lidocaine) if symptoms persist beyond 2 weeks, and reserve surgery only for chronic fissures failing 8 weeks of medical therapy. 1, 2, 3

Initial Conservative Management (First 2 Weeks)

All patients should receive non-operative management as first-line treatment, which heals approximately 50% of acute fissures within 10-14 days 1, 3:

• Dietary modifications: Increase fiber intake and water consumption to soften stools and reduce mechanical trauma 1, 2
• Stool softeners: Use bulk-forming laxatives to prevent constipation 1
• Warm sitz baths: Apply 2-3 times daily to promote sphincter relaxation and increase local blood flow 1, 2
• Topical analgesics: Use lidocaine for pain control, which breaks the pain-spasm-ischemia cycle 2

Pharmacological Treatment (If No Healing After 2 Weeks)

Preferred Agent: Topical Calcium Channel Blockers

Use 0.3% nifedipine with 1.5% lidocaine applied three times daily for at least 6 weeks, which achieves 95% healing rates 2:

• Mechanism: Blocks L-type calcium channels in vascular smooth muscle, reducing internal anal sphincter tone and increasing local blood flow to the ischemic ulcer 2, 3
• Timeline: Pain relief typically occurs after 14 days, with complete healing by 6 weeks 2, 3
• Healing rates: Calcium channel blockers achieve 65-95% healing rates, significantly superior to other topical agents 3
• Cost-effectiveness: Remarkably cost-effective compared to other treatments and surgical interventions 2

Alternative Agent: Glyceryl Trinitrate (GTN)

If calcium channel blockers are unavailable, use 0.2-0.4% GTN ointment twice daily 4, 5:

• Healing rates: Only 25-50%, substantially lower than calcium channel blockers 3
• Major limitation: Headaches occur frequently (17% discontinuation rate in studies), limiting tolerability 5, 6
• Mechanism: NO donor that increases local blood flow and reduces internal anal sphincter tone 1, 4

The evidence shows GTN is less effective than calcium channel blockers with more side effects, making it a second-line choice 3, 5, 6.

Botulinum Toxin Injection

Consider for patients failing topical therapy before proceeding to surgery 3, 7:

• Healing rates: 75-95% with low morbidity 3
• Mechanism: Causes temporary paralysis of anal sphincter muscle for 2-3 months 1
• Limitation: Optimal injection location remains controversial 3

Surgical Management (After 8 Weeks of Failed Medical Therapy)

Lateral internal sphincterotomy is the gold standard for chronic fissures not responding to 8 weeks of conservative treatment 3, 8:

• Indications: Chronic fissures (>8 weeks), acute fissures with severe pain, or recurrent fissures despite optimal medical treatment 3, 8
• Technique: Lateral internal sphincterotomy remains the most effective long-term treatment 8
• Risk: Small but significant risk of anal incontinence, which is why surgery is reserved for medical failures 8

Critical Pitfall to Avoid

Never perform manual dilatation—it is strongly contraindicated due to high risk of incontinence (up to 30%) 1, 3, 8:

This outdated technique causes uncontrolled sphincter damage and should be abandoned entirely 1, 8.

Red Flags Requiring Further Evaluation

Atypical fissures require investigation for underlying conditions 1, 3:

• Location: Lateral fissures or multiple fissures (normal fissures are 90% posterior midline, 10% anterior in women, 1% anterior in men) 1
• Associated conditions to rule out: Inflammatory bowel disease (Crohn's disease, ulcerative colitis), HIV/AIDS, tuberculosis, syphilis, anorectal cancer 1, 3
• Signs of chronicity: Sentinel tag, hypertrophied papilla, fibrosis, visible internal sphincter muscle 3

Treatment Algorithm Summary

1. Weeks 0-2: Conservative management (fiber, fluids, sitz baths, topical anesthetics) 1, 3
2. Weeks 2-8: If not healed, add 0.3% nifedipine with 1.5% lidocaine three times daily 2, 3
3. Week 8+: If still not healed, consider botulinum toxin injection or proceed to lateral internal sphincterotomy 3, 8

This stepwise approach maximizes healing while minimizing the risk of permanent sphincter damage and incontinence 1, 2, 3.