|Type of medicine||Nitrate|
|Used for||Angina |
|Also called||GTN, Coro-Nitro®, Deponit®, Glytrin®, Minitran®, Nitro-Dur®, Nitrolingual®, Nitromin®, Percutol®, Transiderm-Nitro®|
|Available as||Spray, sublingual tablets (for under the tongue), ointment, patches and injection|
Glyceryl trinitrate (GTN) is used for angina. A short-acting preparation (such as a spray or a tablet) is taken to ease angina pain when it happens. Some people take a tablet or a spray before certain types of exercise if they know a pain is likely to develop. Patches are longer-acting and are used regularly to prevent angina pain from occurring.
Angina pain develops if part of your heart muscle does not get as much blood and oxygen as it needs. It is usually caused by narrowing of your coronary arteries due to a build-up of a fatty substance called atheroma. The narrowing makes it more difficult for blood to flow to your heart muscle. GTN works in two ways. It relaxes blood vessels in your body (causing them to widen) and this reduces the strain on your heart, making it easier for your heart to pump blood. It also relaxes and widens the coronary arteries which increases the flow of blood to your heart muscle.
(There is also a rectal ointment of GTN available, but this is used for a completely different condition. See separate medicine leaflet called Glyceryl trinitrate rectal ointment which gives more information about this.)
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start GTN it is important that your doctor or pharmacist knows:
Spray: spray one or two sprays under your tongue when a pain develops. Close your mouth immediately after using the spray. Your pain should ease within a minute or so. If the first dose does not work, take a second after five minutes. If the pain continues for 15 minutes despite taking GTN, then call an ambulance.
Sublingual tablets: place one tablet under your tongue when a pain develops and allow it to dissolve. Your pain should ease within a minute or so. If the first dose does not work, take a second tablet after five minutes. If the pain continues for 15 minutes despite taking GTN, then call an ambulance.
Patches: apply one patch every 24 hours. It is usual to apply the patches to your chest or upper arm, but this may vary depending upon which brand of patches you have been given. If you are in any doubt, check the manufacturer's information leaflet from inside the pack. Use a different area of skin each time you apply a patch. When you use GTN all the time, your body becomes used to it and then it has much less of an effect. To overcome this tolerance, your doctor may advise you remove the patch before you go to bed, to leave your blood free of nitrate in the early hours when you are asleep.
Ointment: use 1-2 inches of ointment (using the measure provided) and apply it to your chest, arm, or thigh every 3-4 hours as required. Use a different area of skin each time you apply the ointment.
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.
|Common GTN side-effects - these affect around 1 in 10 people who take this medicine||What can I do if I experience this?|
|Headache||Ask your doctor or pharmacist to recommend a suitable painkiller|
|Feeling dizzy or weak||Do not drive or use tools or machines|
|Feeling sick||This should soon pass|
|Flushing||If troublesome, speak with your doctor|
If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.