What is the treatment for anal fissure?

Treatment for Anal Fissure

The most effective treatment approach for anal fissure begins with conservative measures including increased fiber intake (30-40g daily), adequate hydration (at least 8 glasses of water daily), and topical calcium channel blockers such as nifedipine or diltiazem applied twice daily for at least 6 weeks, with surgical intervention reserved for cases that fail medical management. 1

First-Line Treatment: Conservative Management

Dietary and Lifestyle Modifications

• Increase fiber intake to 30-40g daily
• Maintain adequate hydration (at least 8 glasses of water daily)
• Use stool softeners and bulk-forming laxatives as needed
• Apply moisturizing agents such as petroleum jelly or zinc oxide as protective barriers 1

Topical Treatments

• Calcium channel blockers (first choice):

  • Nifedipine or 2% diltiazem ointment applied twice daily for at least 6 weeks
  • Healing rates range from 65-95%
  • Mechanism: Reduces internal anal sphincter tone and increases local blood flow 1

• Pain management:

  • Lidocaine (most commonly prescribed topical anesthetic)
  • Warm sitz baths for pain relief 1

• Alternative topical agents (less preferred):

  • Glyceryl trinitrate (nitroglycerin) ointment: Less effective than calcium channel blockers and associated with more headaches and hypotension 1
  • Topical antibiotics (e.g., metronidazole): Reserved for cases with poor therapeutic compliance or poor genital hygiene 1

Second-Line Treatment: Botulinum Toxin

If no improvement after 4-6 weeks of conservative treatment:

• Botulinum toxin injection into the anal sphincter
• High cure rates of 75-95% with low morbidity profile
• More effective than topical treatments but less invasive than surgery 1, 2

Third-Line Treatment: Surgical Intervention

Consider after 8 weeks of failed medical therapy:

• Lateral internal sphincterotomy (LIS):

  • Gold standard surgical procedure
  • Healing rates over 90%
  • Small risk (up to 3%) of minor continence issues
  • Wound-related complications (fistula, bleeding, abscess, non-healing wound) in up to 3% of patients 1, 3

• Fissurectomy with anoplasty:

  • Alternative surgical approach, particularly favored in some regions 3

• Strongly discouraged:

  • Manual anal dilatation (no longer recommended) 1

Treatment Monitoring and Duration

• Continue treatment for at least 6-8 weeks
• Pain relief typically occurs after about 14 days
• Assess response at 2-week intervals
• Consider surgical treatment if non-responsive after 8 weeks of non-operative management 1

Special Considerations

Anatomical Location of Fissure

• Posterior fissures (90% of cases):

  • Respond better to lateral internal sphincterotomy 1

• Anterior fissures (10% of women, 1% of men):

  • Associated with higher probability of underlying external anal sphincter defects
  • Require greater caution with sphincter-weakening procedures
  • Avoid fistulotomy in the anterior perineum of female patients due to high risk of compromising fecal continence 1

Common Pitfalls to Avoid

1. Misdiagnosing anal fissure as hemorrhoids without proper examination
2. Inadequate trial of conservative treatment before progressing to invasive options
3. Premature discontinuation of treatments (need at least 6-8 weeks)
4. Failure to address dietary and lifestyle factors
5. Not recognizing atypical presentations that may indicate other conditions 1

Treatment Efficacy Comparison

• Surgery (LIS): Highest healing rate (>95%) but carries small risk of incontinence 2, 3
• Botulinum toxin: Nearly as effective as surgery without significant adverse effects 2
• Topical calcium channel blockers: 65-95% healing rate with minimal side effects 1
• Topical nitroglycerin: 60-70% effective but associated with headaches 2, 4

Remember that recurrence is possible after any treatment, with rates up to 50% after some medical therapies 5. The treatment approach should follow this stepwise algorithm, progressing to more invasive options only when conservative measures fail.