ANAL FISSURE

• Glyceryl trinitrate ointment works by reducing anal resting pressure, a "chemical sphincterotomy." 80 pts with "chronic" anal fissures randomized to 0.2% GTN ointment BID vs. placebo x 8 wks; 68% healing with GTN vs. 8% with placebo (sig.) 58% of GTN users had headaches at one point but only 1 had to stop tx b/c of this (Lancet 349:11, 1997-JW)

• Botulinum toxin injected into internal anal sphincter: in 30 pts with chronic anal fissure randomized to botox vs. placebo, sig. higher rates of healing (73% vs. 13% and sx relief (87% vs. 27%) at 2mos w/botox. No complications or relapses noted during 16mos of f/u (NEJM 338:217, 1998--JW)

• 50pts with chronic posterior anal fissure randomized to Botulinum toxin (1 injection into each side of internal anal sphincter) vs. 0.2 NTG ointment BID x 6wks. Botulinum toxin group had higher healing rates at 2mos (96% vs. 60%) (NEJM 341:65, 1999--JW)
  
• Topical nifedipine-lidocaine ointment (0.3%-1.5%) Q12h x 6wks vs. topical lidocaine-hydrocortisone ointment Q12h was ass'd with sig. higher healing rates (94.%% vs. 16.4%) in a 6wk randomized trial of 100 ptd with symptomatic anal fissure x > 2mos; no sig. side f/x noted (Dis. Col. Rect. 45:1468, 2002--AFP)
• In a study in 50 pts with chronic anal fissure randomized to nitroglycerin 0.2% ointment BID vs. Botox injections, with crossober to alternative treatment if not healed at 4wks, 2wk response rates were sig. higher in nitroglycerin group (52% vs. 24%) (Am. J. Gastroent. 101:2107, 2006--JW)