0.4% nitroglycerin ointment : in the treatment of chronic anal fissure pain.

0.4% Nitroglycerin ointment is an intra-anal formulation of nitroglycerin (glyceryl trinitrate) indicated for the treatment of chronic anal fissure pain.black triangle Nitroglycerin is a nitric oxide (NO) donor, which reduces the increased anal canal pressure caused by a hypertonic internal anal sphincter, improving anodermal blood flow. A twice-daily 375 mg application of 0.4% nitroglycerin ointment, delivering a daily nitroglycerin dose of 3mg, significantly increased the rate of decrease in mean visual-analogue-scale pain scores, recorded daily, versus placebo (actual vehicle) over the first 3 and 8 weeks of treatment in patients with chronic anal fissure pain participating in randomised double-blind trials. Most recipients of 0.4% nitroglycerin ointment experienced headache, which was transient but severe in 20-25% of patients in randomised double-blind trials; however, compliance was generally good with few study withdrawals. Features and properties of 0.4% nitroglycerin (Rectogesic) rectal ointment Indication Pain associated with chronic anal fissures Mechanism of action Donor of nitric oxide Mediates relaxation of internal anal sphincter Dosage and administration Dosage 375 mg of 0.4% nitroglycerin rectal ointment, delivering nitroglycerin 1.5 mg Frequency Twice daily Route of administration Intra-anal Pharmacokinetic profile Mean bioavailability (0.2% nitroglycerin ointment, 0.75 mg nitroglycerin dose)50%Maximum plasma concentration 0.1 to >1 microg/L Volume of distribution approximate, equals 3 L/kg Clearance approximate, equals 1 L/kg/min Elimination half-life approximate, equals 3 min Most common adverse event Headache.