Management of Anal Fissures
Conservative management with fiber supplementation, adequate fluids, sitz baths, and topical analgesics should be the first-line treatment for all acute anal fissures, as approximately 50% heal within 10-14 days with this approach alone. 1, 2
Initial Assessment and Diagnosis
- Clinical examination with buttock traction is sufficient for typical posterior midline fissures—no routine laboratory tests or imaging are needed 3, 1
- Look specifically for: location (posterior midline vs. atypical lateral position), signs of chronicity (sentinel skin tag, hypertrophied anal papilla, visible internal sphincter muscle at base), and associated conditions 3, 2
- Atypical fissures (off-midline) mandate evaluation for Crohn's disease, HIV/AIDS, ulcerative colitis, tuberculosis, syphilis, leukemia, or cancer 3, 1
- Avoid instrumentation when severe pain is present—it traumatizes the patient and rarely yields diagnostic information 3
First-Line Conservative Management (Weeks 0-2)
Start all patients with this regimen regardless of acuity: 1, 2
- Fiber supplementation to soften stools (age-appropriate foods or supplements) 2
- Adequate fluid intake 1, 2
- Warm sitz baths to relax the internal anal sphincter 4, 2
- Topical lidocaine applied directly to the fissure for pain control 1, 4
- Oral paracetamol if topical anesthetics provide inadequate relief 1, 4
- Consider stool softeners if dietary changes are insufficient 2
Pain relief typically occurs within 14 days, and complete healing occurs in approximately 50% of cases within 10-14 days 1, 4, 2
Second-Line Medical Therapy (After 2 Weeks Without Improvement)
If the fissure persists beyond 2 weeks despite conservative management, escalate to pharmacologic sphincter relaxation: 1, 2
Preferred Option: Topical Calcium Channel Blockers
- Diltiazem or nifedipine ointment with healing rates of 65-95% 1, 2
- These are equivalent to GTN in efficacy but with fewer adverse events 5
Alternative Option: Glyceryl Trinitrate (GTN)
- 0.2% GTN ointment applied twice daily with healing rates of 25-50% 1, 2, 6
- Reduces maximum anal resting pressure from 122.1 to 72.5 cm H₂O within 20 minutes 6
- Major limitation: headaches are common, and late recurrence occurs in approximately 50% of those initially healed 6, 5
Botulinum Toxin Injection
- Botox is equivalent to GTN in efficacy with fewer adverse events 5
- However, it has no established role in acute fissure management in the emergency setting 1
Surgical Management (After 8 Weeks of Failed Medical Therapy)
Lateral internal sphincterotomy (LIS) should only be considered for chronic fissures non-responsive after 8 weeks of conservative management 1, 2, 7
- LIS is the most effective long-term treatment and remains the gold standard, though no medical therapy in randomized trials approached its efficacy 5, 7
- Critical caveat: LIS carries risk of irreversible anal incontinence, making its use controversial 7
- Alternative surgical approaches include fissurectomy combined with anoplasty, calibrated sphincterotomy, or sphincteroplasty to reduce incontinence risk 7
Absolute Contraindications
Manual anal dilatation is strongly contraindicated due to high risk of temporary and permanent incontinence 1, 2, 7
Surgical treatment should never be performed for acute anal fissures 1, 2
Special Populations
Children and Infants
- Same conservative management approach applies 4, 2
- Most heal within 10-14 days with conservative care 4
- Surgical interventions should be avoided in acute fissures in children 2
- Topical antibiotics may be considered in cases of poor genital hygiene 4, 2