Amoxicillin and Co-Codamol: Seizure Risks and Precautions

Amoxicillin rarely causes seizures—mainly in renal impairment (accumulation), high doses, or penicillin allergy (anaphylaxis can mimic seizure).

Co-codamol (codeine + paracetamol) carries seizure risk from codeine, especially:

• Ultra-rapid CYP2D6 metabolizers → high morphine levels
• Renal/hepatic impairment
• High doses or combination with other CNS depressants (alcohol, benzodiazepines, gabapentinoids)
• History of epilepsy

Clinical Advice

• Use lowest effective co-codamol dose; avoid alcohol.
• Monitor for excessive sedation, confusion, myoclonus.
• If seizure occurs: stop co-codamol, seek urgent care.
• Amoxicillin: adjust dose in renal impairment; avoid if prior penicillin anaphylaxis.

Always disclose full medication list to prescriber/pharmacist.