This page follows on from the "Exclusion criteria" statement in the antimicrobial calculators.

Gentamicin:

The following contra-indications and cautions should be taken into account when using the gentamicin calculator.

The gentamicin calculator is not suitable for use in:

• synergistic treatment of endocarditis or Staphylococcal bone infection
• patients treated in Renal units or receiving haemodialysis or haemofiltration
• major burns
• ascites
• age < 16 years o cystic fibrosis (refer to local guidelines), and
• pregnancy (refer to local guidelines).

Contra-indications to gentamicin therapy include:

• hypersensitivity
• myasthenia gravis.

Gentamicin should be used in caution in:

•  Patients with decompensated liver disease - aminoglycosides are associated with an increased risk of renal failure
• Concurrent administration of neurotoxic and / or nephrotoxic agents increases the risk of gentamicin toxicity. Review therapy and consider amending or withholding nephrotoxic drugs during gentamicin treatment.

Avoid co-administration with the following:

• neuromuscular blockers
• other potentially nephrotoxic (e.g. NSAIDs and ACE Inhibitors) or ototoxic drugs
• potent diuretics
• other aminoglycosides.

This list is not exhaustive – consult www.medicines.org.uk for a full list.

• Chronic Kidney Disease (CKD) Stage 4 or more, known or suspected acute kidney injury in the previous 48 hours (³ 50% increase in baseline serum creatinine or oliguria > 6 hours). If gentamicin is clinically indicated, give one dose as per guidance and check with microbiology or an infection specialist before giving a second dose.

Vancomycin

The following contra-indications and cautions should be taken into account when using the vancomycin calculator.

 The vancomycin calculator is not suitable for use in:

• patients treated in Renal Units or receiving haemodialysis or haemofiltration.

Contra-indications to vancomycin therapy include:

• hypersensitivity

 Vancomycin should be used with caution:

• To avoid the risk of “red-neck/red-man syndrome”, pain or muscle spasm, ensure that the administration rate is not faster than 500 mg per hour.
• Concurrent administration of neurotoxic and / or nephrotoxic agents increases the risk of vancomycin toxicity. Review therapy and consider amending or withholding nephrotoxic drugs during treatment with vancomycin. Where possible, avoid co-administration with the following:
  • Amphotericin
  • potent diuretics
  • aminoglycosides
  • NSAIDs
  • ACE inhibitors.

The above list is not exhaustive – consult www.medicines.org.uk

• for a full list
•  Patients with previous hearing loss due to potential ototoxicity.