Antimicrobial stewardship: using antibiotics so resistance stops spreading

Resistance is not created by patients 'building up immunity'. Antibiotics kill susceptible bacteria and leave resistant ones with less competition, so the resistant population grows.

Broad-spectrum antibiotics, particularly cephalosporins, fluoroquinolones and carbapenems, have been repeatedly associated with subsequent MRSA colonisation and infection.

Stewardship is an institutional policy, not individual willpower: restricted formularies, prescribing review at 48–72 hours, IV-to-oral switch, defined durations and rapid diagnostics to narrow therapy quickly.

• Take cultures before starting antibiotics for anything serious, so therapy can be narrowed on the result.
• Review every prescription at 48–72 hours: stop, narrow, switch to oral or continue with a stated end date.
• Use the shortest evidence-based duration; longer is not safer for most infections.
• Avoid antibiotics for viral illness, and avoid treating colonisation or contaminated specimens.
• For patients: finish or stop courses as advised by your clinician, never take leftover antibiotics, and never take someone else's.
• Track consumption and resistance data together so the effect of prescribing changes is visible.

Health systems that introduced restrictive stewardship programmes, particularly reductions in fluoroquinolone and cephalosporin use, reported measurable declines in MRSA rates alongside falls in Clostridioides difficile.

Systematic reviews of stewardship interventions in hospitals find reduced antibiotic use and reduced resistant-organism incidence without worse patient outcomes.

• Adding MRSA cover 'just in case' and never de-escalating when cultures come back negative.
• Treating a positive nasal swab in someone with no infection.
• Keeping leftover antibiotics for the next illness.