Principles of Antimicrobial Treatment

1. This guidance is based on the best available evidence but its application must be modified by professional judgement.

2 A dose and duration of treatment is suggested. In severe or recurrent cases consider a larger dose or longer course.

3 Prescribe an antibiotic only when there is likely to be a clear clinical benefit.

4 Consider a no, or delayed, antibiotic strategy for acute sore throat, common cold, acute cough and acute sinusitis.

5 Limit prescribing over the telephone to exceptional cases.

6 Try to avoid over-use of broad spectrum antibiotics (eg coamoxiclav, quinolones and cephalosporins) as this can increase risk of penicillin non-susceptible pneumococci, Clostridium difficile, MRSA and resistant urinary tract infection (UTIs) and also limit the future usefulness of these important agents. Consider use of narrow spectrum agents (e.g. penicillin, amoxicillin, flucloxacillin, trimethoprim) as outlined in these guidelines for specific indications where clinically appropriate.

In particular, try to reserve use of cephalosporins and quinolones unless there is clear rationale (e.g. where guideline evidence recommends, true allergy with little alternative, specific indication for agent, and/or based on sensitivity results).

7 Note: Hospital antibiotic guidelines can differ from community guidelines as patients are generally systemically unwell when hospitalised and may require intravenous and/or broader spectrum agents due to possible recent exposure to antibiotics in the community and/or failed initial therapy and increased severity of illness.

8 Avoid widespread use of topical antibiotics (especially those agents also available as systemic preparations, e.g. fusidic acid).

9 In pregnancy AVOID tetracyclines, quinolones and high dose metronidazole (2g). Short-term use of trimethoprim (unless low folate status or taking another folate antagonist such as antiepileptic or proguanil) or nitrofurantoin (at term, theoretical risk of neonatal haemolysis) is unlikely to cause problems to the foetus.

10 Clarithromycin has fewer side-effects than erythromycin. However, erythromycin is preferable to clarithromycin if patient is on warfarin. Clarithromycin has a greater potential for raising INR. Note, spectrum of activities of these drugs not identical. Exercise caution when considering concomitant administration of macrolides and statin therapy due to potential risk of rhabdomyolysis.

11 Where a ‘best guess’ therapy has failed or special circumstances exist, seek microbiological advice.