Medicines & Supplements A to Z > Aspirin


Last updated on June 26, 2019.

Overview   |   Dosage   |   Side Effects   |   Where To Buy  

GENERIC NAMES: Aspirin, Acetylsalicylic acid (ASA)



What is Aspirin for?

Aspirin belongs to a class of medications called nonsteroidal anti-inflammatory drugs. It has a wide range of uses including: 

  • Prevention of cardiovascular disease 
  • Management of unstable angina and heart attack 
  • Prevention and treatment of transient ischemic attack (TIA, also known as ministroke) and ischemic stroke 
  • Colorectal cancer prevention
  • Following coronary by-pass surgery 
  • Mild to moderate pain 
  • Fever 

How to use it?

Low-dose Aspirin (325 mg per day or less) is most often used for the prevention and treatment of cardiovascular disease (e.g. heart attacks, stroke, peripheral artery disease) and less often for colorectal cancer prevention. Higher doses of Aspirin are used to manage pain and fever. In general, because Aspirin use has been linked to Reye’s syndrome, Aspirin is no longer recommended for use in children under 16 years of age.

In adults, the usual dose of Aspirin for pain and fever is 300-900 mg every 4-6 hours as required. The maximum daily dose is 4 g per day. 

Aspirin can be taken with food if it causes indigestion or stomach irritation. Your doctor may also prescribe Aspirin with a H2 blocker like Famotidine or a proton pump inhibitor like Omeprazole to reduce stomach upset.

What are the side effects of Aspirin?

The common side effects of Aspirin include nausea, indigestion and bleeding. Chronic use can cause stomach bleeds and kidney injury. Even though Aspirin is available without a prescription, check with your doctor or pharmacist to make sure Aspirin is safe for you to use.

Where to buy Aspirin in Hong Kong?

In Hong Kong, Aspirin is an over-the-counter medicine and can be purchased without a prescription from any retail outlet in Hong Kong. This includes grocery stores, convenience stores, medicine shops, and pharmacies. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Aspirin in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.