What is the comparison between Glyceryl Trinitrate (GTN) and diltiazem for the treatment of anal fissure?

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From the Guidelines

Diltiazem is the preferred treatment for anal fissures due to its higher efficacy and lower risk of side effects compared to glyceryl trinitrate (GTN). According to a recent systematic review and meta-analysis 1, calcium channel blockers (CCBs) such as diltiazem are more effective than GTN in promoting healing and have a lower risk of headache and hypotension. The recommended treatment is 2% diltiazem ointment applied to the anal canal three times daily for 6-8 weeks.

  • Key benefits of diltiazem include:
    • Higher healing rates, ranging from 65 to 95% 1
    • Lower risk of side effects, such as headache and hypotension, compared to GTN 1
    • Improved treatment adherence due to fewer side effects
  • Patients should be advised to combine topical treatment with lifestyle changes, including:
    • Increased fiber intake
    • Adequate hydration
    • Sitz baths
  • If symptoms persist after 8 weeks of topical therapy, surgical consultation for lateral internal sphincterotomy may be necessary.
  • It is essential to note that recurrence is possible, and patients may require retreatment or alternative approaches.

From the Research

Comparison of GTN and Diltiazem for Anal Fissure

  • GTN and diltiazem are two topical treatments used for chronic anal fissures, with the goal of reducing sphincter hypertonia and promoting healing 2, 3.
  • A study comparing topical diltiazem and GTN for chronic anal fissure found that both treatments resulted in comparable healing rates, but diltiazem was superior in terms of reducing headaches and late recurrence rates 3.
  • Another study found that topical diltiazem hydrochloride and GTN were equally effective in healing chronic anal fissure, but diltiazem caused fewer side-effects, particularly headache 4.

Efficacy of GTN

  • A dose-finding study with 0.1%, 0.2%, and 0.4% GTN ointment found that the healing rate was 54.1% for 0.4% GTN, which was statistically significantly different from the placebo group 5.
  • However, the study also found that the definition of "chronicity" needs to be reassessed, as a high proportion of fissures healed in the placebo group 5.

Efficacy of Diltiazem

  • A prospective assessment of 71 consecutive patients with chronic anal fissure treated with 2% topical diltiazem ointment found that 75% of patients experienced healing of the fissure after 2-3 months of treatment 6.
  • Another study found that 48% of patients with chronic anal fissure who had previously failed topical GTN treatment healed with topical diltiazem 2.

Side-Effects

  • Headaches were a common side-effect of GTN treatment, occurring in 27 out of 40 patients in one study 4.
  • In contrast, diltiazem caused fewer side-effects, with only 9 out of 40 patients experiencing headache 4.
  • Perianal dermatitis was a rare side-effect of diltiazem treatment, occurring in 4 out of 71 patients in one study 6.

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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