Glyceryl trinitrate belongs to a group of medicines called organic nitrates. Topical application of glyceryl trinitrate to the anal canal reduces the anal pressure and increases the blood flow, thereby reducing pain.
The usual dose is approximately 375 mg of ointment (approximately 1.5 mg glyceryl trinitrate) applied to the anal canal every 12 hours.
A finger covering, such as a cling film or a finger cot, may be placed on the finger to be used to apply the ointment. The covered finger is placed along side the 1.75 cm dosing line, which is provided on the outside carton, and a strip of ointment the length of the line is expressed onto the end of finger by gently squeezing the tube.
Gently insert the ointment into the anal canal using the finger. The finger with the ointment must be inserted to the first finger joint (approximately 1 cm) into the anus. Treatment may be continued until the pain goes away, or for up to a maximum 8 weeks.