Glyceryl trinitrate (GTN)
Sublingual GTN 400 micrograms for angina and ACS pain if systolic BP above 90. IV infusion for pulmonary oedema with high BP.
On this page
Dose
| Route | Dose |
|---|---|
| Sublingual spray | 400 micrograms (1–2 puffs), repeat after 5 minutes, max 3 doses |
| Sublingual tablet | 300–500 micrograms, repeat as needed |
| IV infusion | 10–200 micrograms/minute, titrated to BP and symptoms |
Cautions
- Avoid if systolic BP below 90, right ventricular infarction, severe aortic stenosis, or sildenafil/tadalafil in the last 24–48 hours.
- Headache, flushing, low BP.
Frequently asked questions
When should GTN not be given?
With systolic BP below 90, right ventricular infarction, severe aortic stenosis or recent PDE5 inhibitor use.
Used in these guides
Sources
Doses on this page are typical doses from the sources above. Always confirm with a current drug reference, the product leaflet and your hospital protocol, especially in children, pregnancy and kidney or liver disease.