glyceryl trinitrate

Last reviewed 01/2018

This is a short-acting nitrate that can be administered sublingually to relieve attacks of angina. It may also be used prophylactically before any activity that precipitates angina.

  • sublingual GTN:
    • rapid onset of action
    • effective for 20-30 minutes
    • dose is 0.3-1mg

  • GTN spray:
    • deliver 0.4mg per metered dose
    • stable for up to 2 years

  • intravenous GTN:
    • infuse at 10-200 micrograms per minute
    • in most patients the dose should be titrated to keep the systolic blood pressure above 90 mmHg

Rarely, methaemoglobinaemia has been associated with prolonged administration.