NZ Formulary

Glyceryl trinitrate (spray)

glis-er-ril try-nye-trate

What does it do?

Glyceryl trinitrate is used to relieve angina. It relaxes the blood vessels, allowing more blood to flow to the heart.

How should you use it?

Stop what you are doing. Sit down and use 1 spray under your tongue.
If your angina is relieved by rest or your spray, you can resume your activities gently.
If after 5 minutes you still have angina, use 1 more spray.
If you still have angina after 5 more minutes, treat as a heart attack – call an ambulance (dial 111) immediately.

Can you take other medicines?

Some medicines available without a prescription may react with glyceryl trinitrate including:

  • sildenafil (e.g. Viagra®) or similar medicines. Taking these and glyceryl trinitrate together may cause severe side effects - discuss this with your health professional.

Tell your pharmacist or doctor about all medicines or treatments that you may be taking, including vitamins, herbal products or recreational drugs.

What side effects might you notice?

Side EffectsRecommended action

Flushing, headache

Fast heartbeat

Fainting, lightheaded

Lie down until these effects pass – tell your doctor if troublesome

If you notice any other effects, discuss them with your doctor or pharmacist.

Other information:

  • Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding.
  • Tell your doctor if you have a history of fainting, or sometimes feel lightheaded.
  • Taking alcohol and glyceryl trinitrate at the same time may increase side-effects.
  • Check the expiry date written on the canister. After this date the spray may not work, so you will need to get a new spray.
  • Keep your glyceryl trinitrate handy at all times, so you know where it is when you need it.
  • You may feel a slight tingling in your mouth when you use glyceryl trinitrate. This is harmless.
  • You may use glyceryl trinitrate before an activity that sometimes causes your angina. Discuss this with your doctor.
  • If you feel lightheaded or faint after using your glyceryl trinitrate, do not drive or operate machinery until this feeling goes away.
  • Some brands need a test spray (priming) before use. Discuss this with your health professional.