Common OTC Painkillers Compared
Three over-the-counter painkillers dominate pharmacy requests: paracetamol, ibuprofen, and aspirin. Each has a distinct safety profile, and choosing the right one for the patient is a core pharmacy skill.
Paracetamol (acetaminophen)
Paracetamol is the safest first-line option for most patients: gentle on the stomach, safe in pregnancy, and with few drug interactions. The main risk is liver damage at doses above 4 g per day (3 g for chronic use or in older adults). Always check for 'hidden' paracetamol in combination cold-and-flu products.
It's the default choice for patients on anticoagulants, with ulcer history, or who are pregnant — where NSAIDs are contraindicated.
Ibuprofen and aspirin
Ibuprofen is effective for inflammatory pain but carries GI, renal, and cardiovascular risks. It interacts with anticoagulants, ACE inhibitors, and diuretics. Avoid in pregnancy (especially after 20 weeks), ulcer history, and kidney disease. Aspirin is similar but also has antiplatelet effects at low doses; it's avoided in children due to Reye's syndrome.
The counselling point for any NSAID: take with food, don't combine with other NSAIDs, and watch for stomach pain, black stools, or swelling.
Practical example
Choosing for a patient on warfarin
A patient on warfarin asks for ibuprofen for back pain. The pharmacist recognises the bleeding-risk interaction and recommends paracetamol instead, within the safe daily limit. The patient leaves with effective pain relief and no added bleeding risk. Same pain, different drug, safer outcome — that's the OTC selection skill.
Key takeaways
- Paracetamol is first-line for most patients — safe, gentle, few interactions.
- Watch for hidden paracetamol in combination products — liver risk.
- Ibuprofen: effective but risky in GI, renal, pregnancy, and with anticoagulants.
- Aspirin is avoided in children (Reye's syndrome) and has antiplatelet effects.
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