Painkillers are not one thing. The three families available without a prescription work differently and carry genuinely different risks, so the useful question is not whether painkillers are safe but which one suits you.
- Paracetamol. Few side effects at label doses. The risk is overdose, which damages the liver and produces no early symptoms. Usually preferred if you have stomach, kidney or bleeding concerns. See paracetamol side effects.
- Anti-inflammatories such as ibuprofen and diclofenac. Better for inflammatory pain, but they irritate the stomach, affect the kidneys, and interact with several common medicines. See NSAID side effects.
- Codeine combinations. Stronger, but cause drowsiness and constipation, and can lead to dependence with regular use.
Common side effects of this pharmacy medicine or category
- Paracetamol: uncommon at label doses; occasionally nausea or rash.
- Anti-inflammatories: indigestion, stomach pain, nausea, fluid retention, headache, dizziness.
- Codeine combinations: drowsiness, constipation, nausea, dry mouth, and reduced concentration.
Across all three, prolonged frequent use for headache can cause medication-overuse headache, where the painkiller sustains the problem it is treating. See long-term painkiller side effects.
Interactions and duplicate-ingredient risks
Codeine-containing painkillers deserve particular attention. In South Africa a number of combination analgesics containing codeine are available from a pharmacy without a prescription, and they are effective, which is part of the problem. With regular use they can cause dependence, and stopping after prolonged use produces withdrawal symptoms that are easily mistaken for the original pain returning.
Two patterns are worth recognising in yourself:
- Medication-overuse headache. Frequent painkiller use for headaches can itself cause headaches, producing a cycle where the treatment sustains the problem.
- Creeping regular use. Buying a packet more often than you used to, using it on most days, or feeling uneasy about running out. None of that requires having done anything wrong; dependence develops from ordinary use.
These products are intended for short-term use, generally a few days at a time. If you have been using one regularly, speak to a pharmacist or doctor rather than stopping abruptly. See codeine side effects and long-term painkiller side effects.
Combination painkillers frequently contain paracetamol, so adding a separate paracetamol tablet doubles the dose. Two anti-inflammatories together add risk without adding benefit, and that includes topical gels alongside tablets. See taking two medicines with paracetamol.
Children, pregnancy, older adults and chronic medicine cautions
- Children. Paracetamol and ibuprofen are dosed by weight; codeine products are generally unsuitable. See children’s paracetamol.
- Pregnancy. Paracetamol is usually preferred; anti-inflammatories are generally avoided, particularly later in pregnancy.
- Older adults. Higher risk of stomach bleeding from anti-inflammatories and of falls from codeine.
- Existing conditions. Ulcer history, kidney disease, heart failure, asthma and blood thinners all steer the choice, usually away from anti-inflammatories.
Warning signs and overdose concerns
Emergency care for: vomiting blood or black tarry stools; severe abdominal pain; difficulty breathing or facial swelling; a blistering rash; very slow breathing or unrousable drowsiness; or any suspected overdose, including paracetamol, even when the person feels completely well.
See a doctor rather than continuing if pain lasts longer than the label allows, is severe, wakes you at night, follows an injury, or comes with fever, weight loss or new weakness. Pain that persists needs a cause, not a longer course.
Questions to ask a pharmacist before using it
- Which of the three families is right for my pain and my health history?
- Does this contain codeine or paracetamol?
- How many days can I take it before being reviewed?
- Do I need stomach protection with an anti-inflammatory?
- Is it safe with my other medicines?
Related OTC and medicine-safety guides
- OTC medicine side effects
- Over-the-counter medicine interactions
- How to read over-the-counter medicine labels
- When to see a doctor about an OTC medicine
- Report an OTC medicine side effect
See also pain and fever medicine side effects and chronic pain medication side effects.
Medical Disclaimer: This content is for informational and educational purposes only and does not constitute medical diagnosis, prescription, or professional advice. Always read the patient information leaflet and consult a qualified doctor or pharmacist regarding any medicine or health concern.