How does aspirin work?
Aspirin blocks an enzyme called cyclooxygenase (COX), which reduces the production of prostaglandins (chemicals responsible for pain and inflammation) and thromboxane (which helps blood clotting). This makes it effective for pain relief and preventing blood clots.
What is aspirin used to treat?
Aspirin is commonly prescribed for:
- Pain relief (such as headaches, muscle pain, and period pain)
- Reducing fever and inflammation
- Preventing heart attacks and strokes (in people at risk of cardiovascular disease)
- Reducing the risk of blood clots after heart procedures (such as stents or bypass surgery)
- Managing conditions like angina and transient ischaemic attacks (TIAs, or mini-strokes)
Who can take aspirin?
Aspirin is suitable for most adults for pain relief and heart protection but should only be taken long-term under medical supervision.
Who might not be able to take aspirin?
Aspirin may not be suitable if you:
- Have a history of stomach ulcers or bleeding disorders
- Have severe kidney or liver disease
- Have asthma that worsens with NSAIDs
- Are allergic to aspirin or similar painkillers
Can I take aspirin if I’m pregnant or breastfeeding?
Aspirin isn’t usually recommended during pregnancy, especially in the third trimester. Low-dose aspirin may sometimes be prescribed under medical supervision. If you’re breastfeeding, speak to your doctor first.
What if I miss a dose?
- For pain relief: Take it as soon as you remember. If it’s close to your next dose, skip the missed one.
- For heart protection: Take it as soon as possible. If it’s almost time for your next dose, skip the missed one—do not take two doses at once.
How effective is aspirin?
Aspirin is highly effective at relieving pain, reducing inflammation, and preventing heart-related complications when taken as prescribed.
What should I do if I take too much?
Taking too much aspirin can cause nausea, ringing in the ears (tinnitus), confusion, or stomach bleeding. If you think you’ve taken too much, seek medical help immediately.
What dose of aspirin is usually taken?
- For pain relief: 300mg to 900mg every 4 to 6 hours (maximum 4g per day)
- For heart attack and stroke prevention: 75mg to 150mg once daily
- For inflammatory conditions (e.g., arthritis): Higher doses may be prescribed by a doctor
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What are the side effects of aspirin?
Common side effects include:
- Stomach irritation or indigestion
- Nausea
- Increased risk of bruising or bleeding
- Ringing in the ears (at high doses)
Serious side effects, such as stomach ulcers, severe bleeding, or allergic reactions, require urgent medical attention.
How should I take aspirin?
Aspirin is taken as tablets (standard or enteric-coated) or dispersible tablets, usually with food or milk to reduce stomach irritation.
When should aspirin be taken?
Aspirin should be taken at the same time each day if used for heart protection, or as needed for pain relief.
What are the brand names for aspirin?
Aspirin is available as a generic medicine, but some branded versions include:
- Disprin
- Nu-Seals Aspirin
- Anadin (in combination painkillers)
Final thoughts
Aspirin is an effective medication for pain relief and heart protection, but it should be taken exactly as prescribed to avoid side effects. If you experience unusual bruising, stomach pain, or other side effects, speak to your doctor or pharmacist.
