Aspirin

NHS information about aspirin, including what it's used for, who can use it, how to use it and side effects.

What aspirin is for

Aspirin is a type of medicine called a non-steroidal anti-inflammatory drug (NSAID).

Aspirin can be:

• taken at a low, regular dose (sometimes called baby aspirin) to prevent blood clots, lower your chance of a heart attack or stroke, and prevent high blood pressure in pregnancy (pre-eclampsia)
• taken at a higher dose, only when you need it, to ease pain

How to take aspirin

Aspirin usually comes as tablets you swallow. There's also a type of tablet you dissolve in water and drink (dispersible tablets).

How much you need to take and for how long depends on why you're taking it.

Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or you have any problems taking it.

If a doctor prescribes aspirin for you, follow the advice they give you about how to take it and how much to take.

How to take aspirin for pain

Aspirin for pain relief usually comes as 300mg tablets.

When taking aspirin for pain:

• take 1 to 3 tablets at a time (ideally with or after food)
• wait at least 4 hours between each dose
• do not take more than 4 doses in a day
• swallow tablets whole with a glass of water – if you're taking dispersible tablets, let the tablet dissolve in a glass of water before swallowing it

Always follow the instructions on the medicine packet.

How to take low-dose aspirin

Low-dose aspirin comes as 75mg tablets.

When taking low-dose aspirin:

• you usually take 1 tablet, once a day
• swallow tablets whole with a glass of water – if you're taking dispersible tablets, let the tablet dissolve in a glass of water before swallowing it

If you're taking low-dose aspirin to prevent a heart attack or stroke, you'll usually need to take it for a long time, sometimes for life.

If you miss a dose of low-dose aspirin

If you forget to take a dose of aspirin, take it as soon you remember, unless it's nearly time for your next dose.

If it's nearly time for your next dose, skip the missed dose and take your next dose at the usual time.

Do not take 2 doses to make up for a forgotten dose.

If you take too much aspirin

Taking an extra dose of aspirin is unlikely to cause problems, but it's important to get medical advice if you take too much as it can sometimes be dangerous.

Side effects of aspirin

Like all medicines, aspirin can cause side effects, but not everyone gets them.

Common side effects

Common side effects of aspirin include:

• indigestion and stomach aches
• bleeding more easily than usual (for example, if you cut yourself it may take longer than usual to stop bleeding)

These are not all the side effects of aspirin.

For a full list, see the leaflet that came with your medicine or search for your medicine leaflet on the electronic medicines compendium website.

You can report any side effects you get on the Yellow Card Scheme website

Who can and cannot take aspirin

Most adults and children aged 16 years or over can take aspirin.

Do not give aspirin to children aged 15 years or under because it can cause a serious condition called Reye's syndrome in rare cases.

Aspirin is not suitable for some people. For example, it may not be suitable if:

• you've had an allergic reaction or serious side effect from aspirin, ibuprofen or another non-steroidal anti-inflammatory drug (NSAID)
• you have a stomach ulcer or you've had them before
• you have asthma
• you have heart failure
• you have a liver or kidney condition
• you have problems with blood clotting

Check the packet or leaflet that comes with your medicine to see if it's suitable for you. Speak to a pharmacist or doctor if you're not sure if you can use it.

Breastfeeding and aspirin

If you're breastfeeding, check with your doctor before taking aspirin at a low dose for blood clots. They may recommend it if the benefits outweigh the risks to your baby.

Taking a higher dose of aspirin for pain is not usually recommended while you're breastfeeding because there's a risk it could cause side effects in your baby. Paracetamol is usually the best painkiller to take if you're breastfeeding.

If you are advised to take aspirin while breastfeeding, speak to a healthcare professional or call NHS 111 if you have any concerns about your baby.

Pregnancy and aspirin

Tell your doctor if you're pregnant or get pregnant while taking aspirin at a low dose for blood clots. You can usually keep taking it up to week 20 of pregnancy, and sometimes later, if your doctor recommends it.

Your doctor may recommend that you take low-dose aspirin from 12 weeks of pregnancy to prevent pre-eclampsia.

Taking aspirin at a higher dose for pain relief is not recommended during any stage of pregnancy. Paracetamol is usually the best painkiller to take if you're pregnant.

Find out more about taking aspirin during pregnancy on the Bumps (Best Use of Medicines in Pregnancy) website:

• Low-dose aspirin during pregnancy (Bumps)
• Aspirin for pain relief during pregnancy (Bumps)

Taking aspirin with other medicines, food and drink

There are some medicines, remedies and supplements that may not mix well with aspirin.

These include:

• anticoagulants (such as warfarin or rivaroxaban)
• some steroid medicines
• some antidepressants
• some medicines to lower blood pressure
• methotrexate, a medicine for rheumatoid arthritis, psoriasis or cancer
• other non-steroidal anti-inflammatory drugs (NSAIDs), such as naproxen or ibuprofen

Before taking aspirin, tell your doctor if you're taking any other medicines, herbal remedies, vitamins or supplements.

Taking aspirin with other painkillers

You can take aspirin at the same time as paracetamol if needed. But if you only need the medicine for pain relief, it's a good idea to try either aspirin or paracetamol on their own first to see if they relieve your pain.

Food, drink and alcohol with aspirin

You can eat and drink normally while taking aspirin, but try to limit the amount of alcohol you drink because alcohol can increase the risk of side effects.

Find out more about your medicine

To find out more about your medicine, you can:

• check the leaflet that comes with it
• search for your medicine leaflet on the electronic medicines compendium website
• speak to a pharmacist or doctor for advice – if you recently started taking it, you can get help with newly prescribed medicines from a pharmacist as part of the New Medicine Service