What's the best way to use GTN spray?

An elderly man with angina clutching his chest

I need to use my GTN spray quite often. Am I using it correctly and how much is too much?

Sunil Kochhar says:

A GTN spray is prescribed to treat angina, which occurs when blood flow to the heart is restricted. If you have angina, you may experience chest pain as a result of everyday exertion. It may also be brought on by other situations like getting stressed at work.

GTN can help to relieve this pain by widening your blood vessels, which increases blood flow to the heart. It is usually taken as a spray, but is also available as a tablet. Either the spray or tablet should be used under the tongue so they are absorbed most quickly. GTN also widens the blood vessels that go to the brain, which can cause some people to get a headache. Although unpleasant, this isn’t anything to worry about.

Use the spray while sitting down to avoid the risk of dizziness and fainting.

The spray can also cause a drop in blood pressure, so use the spray while sitting down to avoid the risk of dizziness and fainting.

If you experience an angina attack, sit down and use your spray. Rest and wait for a few minutes to see if the pain subsides. If the pain doesn’t get better, use the spray again. If you have no pain relief within a few minutes of taking the second dose, or if it gets worse, call 999.

You can use your GTN spray preventatively if you know an activity will bring on your angina, but be aware of how often you are using it, as overuse can reduce its effectiveness. If you find you’re using your spray more frequently, discuss this with your GP or pharmacist, as there may be an underlying issue, and you may benefit from taking a long-acting nitrate medication.

Finally, make sure you check the expiry dates of your medicines, as out-of-date medicines are not effective. A GTN spray has an expiry time of up to three years, whereas GTN tablets expire eight weeks after opening. You can buy GTN medicines from a pharmacy without a prescription if you need to.

Meet the expert: Sunil Kochhar

Image of Sunil Kocchar

Sunil Kochhar is a community pharmacist in the South East of England with more than 20 years’ experience. As well as working in his NHS pharmacy in Kent, Sunil plays an active role in helping communities stay healthy, including educational events, screening services and local health services. 

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