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Aspirin, also known as acetylsalicylic acid, is a widely used medication known for its pain-relieving, anti-inflammatory, anti-platelet and antipyretic properties.

Last Modified: 28 Jun 2024

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What is Aspirin? 

Aspirin, also known as acetylsalicylic acid, is a widely used medication known for its pain-relieving, anti-inflammatory, anti-platelet and antipyretic properties. It works by inhibiting enzymes that produce pain and inflammation-inducing chemicals in the body. 

This drug is part of a group of medications called nonsteroidal anti-inflammatory drugs (NSAIDs). It is synthesized from salicylic acid, which is chemically modified to form acetylsalicylic acid. 

Global Name

The generic name for Aspirin is acetylsalicylic acid. It is available under various brand names including Bayer Aspirin, Bufferin, and Ecotrin. 


What is Aspirin used for? 

Aspirin is used to treat several conditions, including: 
  • Pain relief from headaches, toothaches, muscle aches, and menstrual cramps
  • Reducing fever. 
  • Anti-inflammatory purposes for conditions such as arthritis. 
  • Prevention of heart attacks and strokes by inhibiting platelet aggregation and blood clot formation. 

How do you use Aspirin?  


Aspirin is available in various forms, including tablets, chewable tablets, and extended-release (enteric-coated) tablets.  

Dosage information:

  • Adults: 325-650 mg every 4 to 6 hours as needed for pain or fever. 
  • Atherosclerotic heart disease maintenance: 81 to 325 mg daily 
  • Children: Dosage should be determined by a doctor, with special consideration of the risk of Reye's syndrome (for fever during a viral illness) in patients younger than 19. 


  • Children: Not recommended for viral infections in children under 19 years due to the risk of Reye's syndrome. 
  • Adults: Yes. 
  • Elderlies: Yes, with caution due to increased risk of gastrointestinal bleeding. 
  • Pregnancy: Generally not recommended, especially in the third trimester. 
  • Lactation: Consult a doctor before use. 

Is there anyone who can’t take Aspirin? 

  • Children: Especially those recovering from chickenpox or flu-like symptoms aged 19 below. 
  • Adults: Those with gastric ulcers, hemophilia, or allergy to NSAIDs. 
  • Elderlies: Increased risk of bleeding and kidney issues. 
  • Pregnancy and Lactation: Not recommended unless for specifically prescribed comorbid conditions. 

Allergies: Those allergic to NSAIDs or salicylates should avoid Aspirin. 

Warnings and Precautions:

  • Avoid if you have a history of stomach ulcers or bleeding disorders. 
  • Should be taken with food or a full glass of water to minimize stomach upset. 
  • Do not take together with alcohol as it increases the risk of stomach bleeding. 

Drug and Food/Beverage Interactions

  • Aspirin should not be used with other blood thinners or NSAIDs without medical advice. 
  • Avoid if you take methotrexate or certain antidiabetic medications. 

Side Effects

Common side effects include stomach pain, heartburn, and nausea. Serious side effects may include bleeding in the stomach, ulcers, and allergic reactions.

Pharmacist Tips

Storage information: 
Store at room temperature away from moisture and heat. 

Handling instructions: 
Keep Aspirin in its original package. Follow the dosage instructions carefully, and do not exceed the recommended dose without consulting a healthcare provider


Where is Aspirin available in Hong Kong?

Aspirin is an over-the-counter (OTC) medication that can be sold without a prescription. It is available in all chain drug stores, including Mannings and Watsons. 



Can I take Aspirin for a headache? 

Yes, Aspirin can be effective for relieving headaches.

How long does it take for Aspirin to work? 

Aspirin generally starts to relieve pain within 15 to 30 minutes after ingestion.

Can Aspirin prevent heart attacks?

Yes, Aspirin can help prevent heart attacks by thinning the blood, but it should only be used for this purpose under medical advice.

Is it safe to take Aspirin daily?

Daily use of Aspirin should be based on medical advice, particularly for those using it for cardiovascular protection.

This website provides content related to drug use and medicine for informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Do not use the information on this website to diagnose or treat a health problem or disease without consulting a qualified healthcare provider. The website's owners and contributors are not liable for any repercussions, adverse effects, or consequences resulting from the use of any medication or information provided herein.

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