A B C D E F G H I J K L M N O P R S T U V W

ANGINA DRUGS

What are the types of Angina Drugs ?

Glyceryl trinitrate (GTN), as found in Coro-nitro, Glytrin, Nitromin, Minitram, Percutol, Nitrolingual, Nitro-Dur, Deponit, Transiderm Nitro, Sustac, Nitrocontin and Suscard. Isosorbide dinitrate (ISDN), as found in Angitac, Sorbid, Isoket, Sorbitrate, Sorbichew, Isordil and Cedocard. Isosorbide mononitrate (ISMN), as found in Isotrate, Chemydur, Imdur, Isib, Isotard, MCR, Modisal, Monomax,m Monosorb, Imazin, Elantan, Ismo, Monit and Mono-Cedocard.

What are Angina Drugs for ?

Nitrates are used to treat and prevent angina. This is chest pain caused by not enough blood (and therefore not enough oxygen) reaching the heart muscle. This is usually due to the coronary arteries supplying the heart being narrowed by a fatty lining (atheroma): a form of hardening of the arteries. Sometimes the narrowing is due to a muscular spasm of the coronary arteries. They may also be used to improve functioning of the heart.

How do Angina Drugs work ?

Nitrates help to keep the coronary arteries as wide open as possible, so that as much oxygen as possible gets to the heart to relieve the pain. Nitrates also open up other arteries in the body. This makes it easier for the heart to pump blood around the body, putting the heart under less strain. It then can get by with less oxygen.

How should Angina Drugs be used ?

Nitrates can be used either to relieve or prevent attacks of angina. If you do not get very frequent attacks, your doctor will probably give you quick-acting nitrates (GTN) to dissolve under your tongue or as a mouthspray to spray under your tongue. You should take these as soon as you feel a chest pain coming. This should stop the pain before it gets too bad. If you know what is likely to bring on an angina attack, you can either avoid doing it or take GTN before doing it so that the pain is prevented. If your angina occurs more often, more severely or if your heart does not appear to be functioning as well, your doctor is more likely to give you one of the ISMN or ISDN preparations listed above to take regularly. This should help prevent the pains. In addition, you may be given other medication: beta-blockers and calcium channel blockers are described in other leaflets (23.4 and 23.3). Long-acting nitrates can be taken as tablets or capsules, patches or ointment. The drug seeps slowly out of the patch, through the skin and into the blood-vessels. A new patch is needed every day. Your doctor may advise you not to have a patch for a certain number of hours each day. This is to avoid your body getting too used to the drug. This could make the nitrate less effective in controlling your angina. Nitrates (and other drugs) can control angina, but not cure it. You will always need the drugs, unless you have surgery to improve the blood flow to the heart.

During Treatment with Angina Drugs

You should find that quick-acting tablets or mouthspray stop any chest pain very quickly. On ISMN or ISDN, your attacks should come on less frequently and less severely. You may find that you can do things that you were not able to do before treatment. Most side-effects of nitrates are worst when you first start taking them. They will tend to disappear as you continue to take them. Headache, flushing and dizziness are the worst offenders! The dizziness is due to a fall in blood pressure. Tell your doctor, who will check your blood pressure and probably reduce the dose. Try taking the first few doses while sitting down: this will help to get you used to them.

Drug Interference

If you take a nitrate with any other blood pressure lowering tablet, there is a possibility of dizziness, due to a fall of blood pressure. You may even faint. A few other drugs which you could be taking (particularly antidepressants) could cause a dry mouth. This could stop a GTN tablet from dissolving. A spray would get around the problem. Nitrates should not be taken at the same time as sildenafil (Viagra), a drug to treat male impotence. If you are taking sildenafil, contact your doctor or pharmacist before taking any nitrate.

What if Angina Drugs are not taken ?

You should not stop taking your regular ISMN or ISDN treatment unless your doctor advises it. Chest pains are likely to return, and you could even bring on a heart attack. If you forget to take a dose of ISMN or ISDN at your usual time, take it as soon as you remember. If less than 2 hours until your next dose is due, take one dose now and miss the next. If you forget to change your patch at the usual time, change it as soon as you remember. Change to the new patch at the usual time.

General advice on Angina Drugs

GTN tablets only keep for 8 weeks once the bottle has been opened. They also react with plastic. They should therefore be kept in the original glass bottle with the lid screwed on tightly. If you find that they do not seem to work as well as they did, try a new bottle (you can buy them from a pharmacy if you do not wish to trouble your doctor for a new prescription). If the new supply does not help either, then different treatment may be needed and you should see your doctor. If there are any questions not dealt with in this leaflet, please ask your pharmacist or doctor. Keep this leaflet handy in case you need to refer to it at a later date.