Angina: treating symptoms and emergency treatment
Angina pain or discomfort is a symptom of underlying heart problems, usually caused by narrowed or blocked coronary arteries. It must not be ignored, as it may be a sign of an impending heart attack.
Types of angina
Angina can be classified as stable if the pattern of angina symptoms has not changed over the past month.
Stable angina eases when you rest. You will usually know what brings it on, such as walking up stairs or uphill. The pain usually goes after a few minutes — it should not last longer than 10 minutes. Your angina medicine should take this pain away.
Stable angina doesn't usually damage the heart muscle.
Unstable angina is not as predictable. It may happen when one or more of the coronary arteries become even more blocked than they were before. The angina pain may occur in situations where it hasn't happened before, or during periods of minimal exertion or even rest. For example, it may wake you in the middle of the night.
Unstable angina may lead to a heart attack which results in permanent damage to the heart muscle.
A change in the pattern of your angina is very important and you should seek medical attention. If you also feel faint, sweaty or breathless, call an ambulance by dialling 000 immediately.
Several different types of medicines are used to treat angina:
- Medicines to treat angina symptoms.
- Medicines to stop you from having further attacks of angina and to help lower your risk of having a heart attack.
Treating angina symptoms
If you experience angina symptoms, you should stop whatever activity you are doing and rest.
Nitrates are the most common way to treat angina. Nitrate spray or nitrate tablets that dissolve under your tongue are used when you first start to feel the symptoms of angina.
Nitrates work quickly by relaxing the blood vessels, opening them wider so blood can flow more freely.
Your doctor may give you a nitrate spray called glyceryl trinitrate (brand name Nitrolingual Pumpspray). The spray delivers a measured dose of nitrate under your tongue each time the nozzle is pressed.
The spray droplets are absorbed quickly and give an almost immediate effect. Follow the instructions to ensure that you receive the correct dose.
You should sit or lie down before taking nitrates, because these medicines can reduce your blood pressure and can make you feel light-headed or faint.
If the angina is not relieved after 2 doses (with a 5 minute interval between each spray), take a third dose and call an ambulance. Dial 000 immediately.
Nitrate tablets used to treat angina symptoms include:
- glyceryl trinitrate tablets (brand names include Anginine); and
- isosorbide dinitrate tablets (brand name Isordil Sublingual Tablets).
These tablets are absorbed into the bloodstream through the lining of your mouth.
The chemist’s label will tell you the correct dose, but check with your doctor if there’s something you don’t understand.
To use glyceryl trinitrate or isosorbide dinitrate tablets effectively:
- place the tablet under your tongue or in your cheek and allow it to dissolve;
- do not swallow, chew or crush your tablet; and
- avoid eating, drinking or smoking until the tablet has completely dissolved.
If the angina is not relieved by a total of 2 tablets and rest in 10 minutes, take a third dose and dial 000 immediately for an ambulance.
Storing your nitrate spray or tablets
- Check the expiry date on all medicines. Always have enough medicine on hand, and carry the spray or tablets with you at all times.
- Be aware that heat or dampness can adversely affect some medicines. Store nitrate spray and tablets in a cool, dry place below 25°C. Do not leave in a car on hot days.
- Glyceryl trinitrate tablets start to lose their effectiveness 3 months after the bottle has been opened, so replace them at this time. It is a good idea to write the date you opened the bottle on the label as a reminder.
- Keep nitrate tablets stored in the glass bottle in which they were dispensed. They should not be exposed to warmth, light or air. Don't place any other material, even cotton wool in your glyceryl trinitrate tablet bottle: use only the special packing provided.
Side effects of nitrates
The most common side effects of short-acting nitrates are:
- low blood pressure (feeling faint or dizzy);
- flushing (redness of the face); and
- palpitations (an awareness of your heart beating or pounding in your chest).
Spitting out the nitrate tablet once symptoms are relieved may relieve these side effects. If you continue to experience side effects, check with your doctor.
Nitrate tablets and sprays temporarily lower your blood pressure. For this reason you may feel a bit faint if you are using them for the first time, if you take too much, or when you are hot (such as after a shower). It's best, therefore, to sit down when taking them.
You should be careful if you drink alcohol while taking nitrate medicines as it may increase the likelihood of faintness and dizziness.
If you are taking nitrates, do not take certain medicines used to treat erectile dysfunction – sildenafil (brand names Viagra, Vedafil), tadalafil (brand name Cialis) or vardenafil (brand name Levitra) – because serious, even fatal, side effects may occur.
If you are concerned about the side effects of your medicines, consult your doctor.
Angina action plan
Occasional angina symptoms: action plan
- Stop what you are doing, sit down, rest and wait until the feeling passes. If you have been given a nitrate spray or tablets, use them as instructed.
- If you are using the spray, and the angina persists for 5 minutes after the first dose, you can administer a second dose. Resume your activities gently once the symptoms have passed.
- If you are taking the nitrate tablets, you can use up to 2 tablets, 5 minutes apart, to relieve the angina pain. Always follow your doctor's instructions. These will usually be to use one tablet to start with — allow it to dissolve under your tongue or inside your cheek.
- If 2 doses of spray or tablets don't relieve the angina, take a third dose and call an ambulance immediately.
- If your angina is accompanied by significant breathlessness, palpitations or a feeling that you are about to pass out, call an ambulance immediately.
Regular pattern angina symptoms: action plan
Some people get angina at predictable times. For example:
- when it's cold;
- when walking up hills or stairs;
- while working or doing chores;
- while showering; or
- during sexual activity.
Use your nitrate spray or tablets a few minutes before attempting the activity that triggers your angina. If you are experiencing angina symptoms every day, consult your doctor so that further preventive treatment can be planned.
Change in angina symptoms: action plan
The pattern of your angina may change significantly in the following ways. It may:
- happen more often;
- be more severe;
- happen at rest or at night; or
- not be relieved as easily as usual by your angina medicine.
This is called unstable angina, and may be a warning sign of impending heart attack. You should seek medical help immediately.
Last Reviewed: 14/05/2015
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3. Secondary prevention of cardiovascular events (revised February 2012. Amended October 2012). In: eTG complete. Melbourne: Therapeutic Guidelines Limited; 2015 Mar. http://online.tg.org.au/complete/ (accessed Apr 2015).
4. MayoClinic.com. Angina (updated 3 Feb 2015). http://www.mayoclinic.com/health/angina/DS00994/ (accessed Apr 2015).