Low-dose aspirin is a blood-thinning medicine. It helps prevent heart attacks and strokes if your risk of getting these is high. Aspirin is also known as acetylsalicylic acid.
Taking low-dose aspirin to prevent heart attacks and strokes is not the same as taking aspirin as a painkiller. Low-dose aspirin does not act as a painkiller.
Low-dose aspirin comes as tablets and is only available on prescription. You take it daily.
It's also known by the brand names Nuprin and Nu-seals.
Low dose aspirin also comes in a mixed tablet with other heart medicines such as statins or clopidogrel. The mixed tablets are only available on prescription.
Important
Only take daily low-dose aspirin if your GP prescribes it.
When you start taking low-dose aspirin
You may not notice any difference in how you feel after you start taking low-dose aspirin. This does not mean that the medicine is not working.
Keep taking low-dose aspirin even if you feel well. You will still be getting the benefits.
Take it with or just after food so it does not upset your stomach.
Drinking alcohol
You can drink alcohol while taking low-dose aspirin. But alcohol can irritate your stomach.
Do not drink more than the weekly low-risk alcohol guidelines.
Check if you can take low-dose aspirin
Low-dose aspirin is sometimes called baby aspirin because of the small dose, but it's not safe for children.
Important
Never give aspirin to a child under age 16, unless their GP prescribes it. Aspirin can be linked to Reye's syndrome in children. This is a very rare condition that affects the brain and liver.
Before your GP prescribes low-dose aspirin tell them if you:
- have any medical conditions including asthma, lung disease or a blood-clotting disorder such as haemophilia
- had an allergic reaction to medicine in the past
- have heavy periods
- are pregnant or trying to get pregnant
- are breastfeeding
- have a history of stomach ulcers or gastrointestinal bleeding after taking certain medicines, including aspirin or ibuprofen
Pregnancy and low-dose aspirin
Talk to your GP or pharmacist before taking aspirin if:
- you are pregnant
- think you might be pregnant
- trying to get pregnant
You should not take aspirin while pregnant unless your GP tells you to.
They may advise you take it during pregnancy:
- to help prevent heart attack and stroke
- to help prevent pre-eclampsia (high blood pressure in pregnancy)
- if you're having fertility treatment
- if you have had several miscarriages
Low-dose aspirin is not approved for these uses. But your GP may decide to use it if they think the potential benefits to your health outweigh the risks. This is known as off-label use. Talk to your GP or pharmacist about off-label use.
What off label means
Off-label use is when a medicine is prescribed in a way that is different to how it was first licensed.
Your GP may prescribe a medicine off label if they think it will treat your condition effectively.
They prescribe the medicine in a different way than described on the patient information leaflet, such as:
- for a different age group
- to treat another condition
- at a higher or lower dosage
Off-label use does not mean that the medicine is unsafe. Your GP will tell you if they are prescribing the medicine off label. They will only prescribe it if the benefits outweigh any risks.
Talk to your pharmacist or doctor if you have any concerns or questions about off-label use.
Breastfeeding and low-dose aspirin
If you are breastfeeding, talk to your GP or pharmacist before taking aspirin.
Aspirin is not recommended while you're breastfeeding.
But your GP may suggest that you take low-dose aspirin while you're breastfeeding if they think the benefits of the medicine outweigh the possible harm.
How and when to take low-dose aspirin
Always take low-dose aspirin exactly as your GP has advised.
You'll usually take low-dose aspirin once a day. Most people will need to take it for the rest of their life.
Do not take it on an empty stomach. It's best to take it with or just after food. This will make it less likely to upset your stomach.
Low-dose aspirin tablets have a special coating to help avoid an upset stomach. Do not chew or crush them because it'll stop the coating working.
If you also take indigestion medicines, take them at least 2 hours before or after you take your aspirin. The antacid in the indigestion medicine affects the way the coating on these tablets works.
If you forget to take it
Do not take a double dose to make up for a forgotten dose.
If you forget to take a dose of aspirin, take it as soon as you remember. If you do not remember until the following day, skip the missed dose.
If you take too much
Taking 1 or 2 extra tablets by mistake is unlikely to be harmful.
Urgent advice: Call your GP straight away if you take too much aspirin and have side effects such as:
- feeling sick (nausea)
- ringing in your ears (tinnitus)
- hearing problems
- confusion
- dizziness
- fast breathing
- high temperature of 38 degrees Celsius or higher (fever)
If you need to go to an emergency department (ED), do not drive yourself. Get someone else to drive you or call 112 or 999 for an ambulance.
Bring the aspirin packet or leaflet inside it, along with any remaining medicine with you.
Side effects
Talk to your GP, a pharmacist or nurse if side effects bother you or do not go away.
Common side effects
There are things you can do to manage common side effects:
Mild indigestion
Take your aspirin with food. If the indigestion still does not go away, it could be a sign that the aspirin has caused a stomach ulcer. Talk to your doctor. They may prescribe something to protect your stomach or switch you to a different medicine.
Diarrhoea
Drink lots of fluids, such as water or squash, to avoid dehydration. Signs of dehydration include peeing less than usual or having dark, strong-smelling pee.
Do not take any other medicines to treat diarrhoea without speaking to a pharmacist or GP.
If you take the combined contraceptive pill or the progestogen-only pill and you have severe diarrhoea for more than 24 hours, your contraception may not protect you from pregnancy. Check the pill packet for advice.
Feeling sick (nausea)
Stick to simple meals and do not eat rich or spicy food. Make sure you take aspirin with some food.
Getting sick (vomiting)
If you are getting sick, try small, frequent sips of water to avoid dehydration. Signs of dehydration include peeing less than usual or having dark, strong-smelling pee.
If you take the combined contraceptive pill or the progestogen-only pill and you're getting sick, your contraception may not protect you from pregnancy. Check the pill packet for advice.
Constipation
Try to get more fibre into your diet, such as fresh fruit and vegetables and cereals, and drink plenty of water. Try to exercise more regularly, for example by going for a daily walk or run.
If this does not help, talk to your pharmacist or GP.
Loss of appetite
Try to eat at your usual meal times even if you do not feel hungry. If this becomes a problem, speak to your GP or pharmacist.
Bleeding more easily than normal
Be careful when doing activities that might cause an injury or a cut.
Always wear a helmet when cycling. Wear gloves when you use sharp objects like scissors, knives, and gardening tools. Use an electric razor instead of wet shaving, and use a soft toothbrush and waxed dental floss to clean your teeth.
Talk to your GP if you're worried about any bleeding.
Stomach ulcers
Aspirin can cause ulcers in your stomach or gut, especially if you take it for a long time.
If you're at risk of getting a stomach ulcer, your GP may prescribe a medicine to help protect your stomach.
They may tell you not to take aspirin if you have a stomach ulcer, or had an ulcer in the past.
Serious side effects
Serious side effects are rare.
Urgent advice: Call your GP straight away if you:
- get red, blistered or peeling skin
- cough up blood or you have blood in your pee, poo or vomit
- have jaundice (your skin or white of your eyes turn yellow) - this can be a sign of liver problems
- have painful joints in your hands and feet - this can be a sign of high levels of uric acid in the blood
- have swollen hands or feet - this can be a sign of water retention
Read the patient information leaflet that comes with your medicine for a full list of side effects.
Non-urgent advice: Find your patient information leaflet
Your patient information leaflet is the leaflet that comes with your medicine. You can find a digital version of the leaflet online.
Report side effects
You can report any suspected side effects to the Health Products Regulatory Authority (HPRA): report an issue - hpra.ie
Serious allergic reaction
A serious allergic reaction to aspirin is rare.
Emergency action required: Call 112 or 999 or go to an emergency department if:
- you get a rash that is itchy, red, swollen, blistered or peeling
- you're wheezing
- you get tightness in the chest or throat
- you have trouble breathing or talking
- your mouth, face, lips, tongue or throat start swelling
These are signs of a serious allergic reaction. You might need to go to hospital.
Taking low-dose aspirin with other medicines
Some medicines interfere with the way low-dose aspirin works.
If you’re on any other medicines or supplements, check with your GP, a pharmacist or nurse before you start taking low-dose aspirin.
Taking painkillers
It's safe to take paracetamol with low-dose aspirin.
Do not take ibuprofen at the same time as low-dose aspirin without talking to your GP.
Aspirin and ibuprofen both belong to the same group of medicines called non-steroidal anti-inflammatory drugs (NSAIDs).
Taking them together can increase your chances of side effects such as stomach irritation.
Fact check
This content was fact checked by a pharmacist, a GP, the National Medication Safety Programme (Safermeds) and the Health Products Regulatory Authority (HPRA).
