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ASA (Acetylsalicylic Acid)

Your child needs to take the medicine called ASA (acetylsalicylic acid, say: a-SEE-ta-sal-a-si-lik). This information sheet explains what ASA does and how to give it to your child. It also explains what side effects or problems your child may have when he or she takes this medicine.

What is ASA?

ASA may be used to treat or prevent strokes that happen because of blood clots. It acts by keeping platelets in the blood from sticking together.

ASA may also be used to reduce fever, pain, and inflammation (redness and swelling).

You may also hear ASA called by its brand name, Aspirin®.

How should you give your child ASA?

Follow these instructions when giving your child ASA.

  • Give your child ASA regularly, exactly as your doctor or pharmacist tells you. Avoid missing doses by giving your child ASA at the same time each day.
  • Talk to your child’s doctor before you stop giving ASA for any reason.
  • Make sure you have enough ASA to last through weekends, holidays, and vacations.
  • Give your child ASA with food or milk so his or her stomach does not become upset.
  • If your child is taking the regular tablets or Children’s Aspirin®, they may be swallowed whole, crushed, or chewed. Make sure your child drinks a glass of water or milk after taking the ASA.
  • If your child is taking the enteric-coated ASA, the tablets should be swallowed whole with a glass of water, not crushed or chewed.

What should you do if your child misses a dose of ASA?

  • Give your child the missed dose as soon as you remember.
  • If it is almost time for the next dose, skip the missed dose.
  • Give your child the next dose at the regular time.
  • Give your child only 1 dose at a time.

What are the possible side effects of ASA?

Your child may have some side effects while he or she takes ASA. Usually your child will not need to see a doctor about them.

These mild side effects may go away as your child’s body gets used to ASA. Check with your child’s doctor, and follow his or her instructions if your child has any of these signs or symptoms and they do not go away or they bother your child:

  • a rash or itchy skin
  • mild stomach cramps (usually happens shortly after taking a dose)
  • upset stomach or throwing up

Most of the following side effects are not common, but they may be a sign of a serious problem. Call your child’s doctor right away or take your child to the Emergency Department if your child has any of these side effects:

  • severe or lasting stomach pain
  • black, tarry stools
  • difficulty breathing
  • severe sweating
  • problems seeing, blurred vision
  • dizziness
  • ringing in the ears, trouble hearing

What other important information should you know about ASA?

Before starting ASA, tell your child’s doctor if your child has ever had asthma. Also tell your child’s doctor and pharmacist if your child has ever had any unusual or allergic reaction to ASA or any other medicines.

Tell your child’s doctor if your child has ever had bleeding from the stomach or frequent stomach aches.

ASA should not usually be given to a child with a fever who has a viral illness such as chickenpox or flu (influenza). Check with your child’s doctor before giving ASA if your child seems to be coming down with a virus. The doctor may tell you to change the amount of ASA that you give your child.

Check with your child’s doctor or pharmacist before you give your child any other medicines, even medicines that you can buy without a doctor’s order (prescription), such as cough medicines. Ask your doctor or pharmacist before you give your child any herbal products because they can increase or decrease your child’s response to ASA.

Before your child has any kind of surgery, even on the teeth, or emergency treatment, tell the doctor or dentist that your child is taking ASA. If they tell you to stop the ASA, speak to your child’s doctor or dentist about when is the right time to start taking ASA again.

Keep all appointments at the clinic or doctor’s office and for blood tests, so that the doctor can check your child’s reaction to ASA.

Keep this medicine at room temperature. Keep it away from damp places, such as the bathroom or the kitchen sink.

Do not give your child any ASA that has changed color or that smells of vinegar. Ask your pharmacist about how to throw away any ASA that has gone bad or is out of date.

Throw away any ASA that is out of date.

Keep all medicines out of your child’s sight and reach.

If your child takes too much of any medicine, call the Ontario Poison Centre at one of these numbers. These calls are free.

  • Call 416-813-5900 if you live in Toronto.
  • Call 1-800-268-9017 if you live somewhere else in Ontario.
  • If you live outside of Ontario, call your local Poison Information Centre.

Disclaimer: The information in this Family Med-aid is accurate at the time of printing. It provides a summary of information about ASA and does not contain all possible information about this medicine. Not all side effects are listed. If you have any questions or want more information about ASA, speak to your healthcare provider.

Elaine Lau, BScPhm, PharmD, MSc, RPh