Painkillers may speed antibiotic resistance with ciprofloxacin

Researchers at the University of South Australia report that two ubiquitous over the counter painkillers, ibuprofen and acetaminophen, can accelerate the development of antibiotic resistance in laboratory tests, particularly when combined with the broad spectrum antibiotic ciprofloxacin. The study, published this month in the journal npj Antimicrobials and Resistance, found that exposure to these common nonantibiotic drugs increased mutation rates in Escherichia coli and produced high levels of resistance not only to ciprofloxacin but to multiple antibiotic classes.

In controlled laboratory experiments, scientists exposed E. coli to ciprofloxacin alone and in combination with a range of nonantibiotic medications. When ibuprofen or acetaminophen were present, bacteria developed more genetic mutations than with the antibiotic alone, enabling faster growth and greater antibiotic tolerance. The researchers also identified genetic mechanisms that appear to be involved: both pain relievers activated bacterial defenses that help expel antibiotics, reducing drug effectiveness.

Lead author Rietie Venter, an associate professor at UniSA, said the findings show antibiotic resistance is...