Overview

• Ibuprofen and paracetamol drove resistance on their own and amplified it when combined with the antibiotic ciprofloxacin in E. coli experiments.
• E. coli exposed to the painkillers plus ciprofloxacin developed significantly more mutations and became highly resistant to the antibiotic.
• Cross-resistance was observed to multiple other antibiotic classes, raising concerns about broader treatment failure.
• Genetic analyses showed the painkillers activated bacterial drug‑expelling defenses that reduce antibiotic effectiveness.
• The study evaluated nine medications common in residential aged care, and the authors urge expanded research while not recommending stopping necessary painkillers.