Sounds like 'AS-pir-in'

Easy-to-read medicine information about aspirin – what is it, how to take aspirin safely and possible side effects.

Type of medicine Also called
  • Blood-thinning medication
  • Belongs to a group of medicines known as anti-platelets
  • Aspec®
  • Cartia®
  • Aspirin (Ethics)®
  • Cardiprin®

What is aspirin?

  • Low strengths of aspirin or low dose aspirin is used as a 'blood thinner' to prevent clots forming in blood vessels.
  • In this way low-dose aspirin reduces the risk of stroke and heart attack.
  • It is especially effective if you have had a heart attack, angina (chest pain), stroke or transient ischemic attack (TIA or mini-strokes). Taking low-dose aspirin reduces the risk of a further event by about 25% over 5 years.


  • The usual dose is one low-dose aspirin tablet (75 milligrams or 100 milligrams) each day.

How to take aspirin

  • Take aspirin at the same time each day.
  • Some aspirin tablets have a special coating, to reduce the risk of stomach irritation. These are called 'enteric coated' or EC tablets.
  • If you are taking a coated aspirin tablet, swallow the tablet whole with a glass of water. Do not crush or chew. This affects the special coating. 
  • It does not matter if you take the coated aspirin tablets with or without food. 
  • If you have been given dispersible tablets, stir each tablet in a glass of water and swallow when dissolved.  
  • Take the dispersible aspirin tablet with or after a meal or snack.
  • If you miss a dose, take it as soon as you remember that day. Do not take 2 doses on the same day. 

Possible side effects

Like all medicines, aspirin can cause unwanted side effects, although not everyone gets them. Often unwanted side effects improve as your body gets used to the new medicine.

Side effects What should I do?
  • Stomach upset or indigestion
  • Try taking aspirin with or after a meal
  • Tell your doctor if troublesome
  • Dark coloured vomit, dark stools (poo), unusual bleeding or bruises 
  • Tell your doctor immediately or ring HealthLine
  • Signs of an allergic reaction such as skin rash, itching, swelling of the lips, face, and mouth or difficulty breathing
  • Tell your doctor immediately or ring HealthLine


  • Aspirin may interact with medicines available without a prescription such as anti-inflammatories for example ibuprofen, diclophenac, naproxen. 
  • Aspirin may also interact with other medications and herbal supplements, so check with your doctor or pharmacist before starting aspirin or before starting any new medicines. 

Learn more

New Zealand Formulary Patient Information:

Aspirin (low dose)

Credits: Sandra Ponen, Pharmacist. Reviewed By: Dr J Bycroft. Health Navigator NZ Last reviewed: 08 Jan 2015