Vancomycin

Oral vancomycin is used only to treat Clostridioides Difficile (C. diff) Infection. 

Dose for mild, moderate or severe C. diff is 125mg po QDS for 10 days. 

Dose for life-threatening C. diff is 500mg po QDS (used with metronidazole IV). Usual duration of treatment is 10 days but all cases of life-threatening C. diff must be discussed with Micro ID.

Dose adjustment is not needed for oral vancomycin in renal impairment patients.

For patients with enteral feeding tube or swallowing difficulties order vancomycin liquid from pharmacy.

Cautions/ Contraindications:

Use with caution in patients with renal impairment and those with a history of deafness. Use nephrotoxic drugs with caution alongside vancomycin e.g. ACE-inhibitors, amikacin, ciclosporin, colistimethate sodium, diuretics, gentamicin, NSAIDs, radio-contrast media, high-dose methotrexate or amphotericin B liposomal (Tillomed/Gilead/AmBisome).

Adverse effects:

• Nephrotoxicity
• Ototoxicity
• Blood disorders (including neutropenia, thrombocytopenia and agranulocytosis).
• Skin rash
• Thrombophlebitis (usually on rapid administration). 

Pregnancy:

Use only if potential benefit outweighs risks. Vancomycin level monitoring is essential to reduce risk of foetal toxicity.

Hepatic impairment:

Dose adjustment is not required.

Renal impairment:

Dose of IV vancomycin must be reduced in renal impairment. See 'eGFR less than 20mL/min/1.73m² or dialysis' section.

(N.B. For patients with eGFR less than 20mL/min/1.73m² or dialysis, see 'eGFR less than 20mL/min/1.73m² or dialysis' section below)

STEP 1. Select a loading dose                                                                                                                          

Use the EPR Vancomycin IV (Adult): Initial therapy - loading dose and initial maintenance dose PowerPlan.

Loading doses (25-30mg/kg Actual Body Weight) are recommended for all patients with an eGFR  20mL/min/1.73m² or more. For patients with eGFR less than 20mL/min/1.73m² or dialysis, see section below.

Use the table below to select the correct loading dose for patients 35kg or above with an eGFR of 20mL/min/1.73m² or more. For patients weighing under 35kg, contact Micro/ID.

STEP 2. Select an initial maintenance dose                                                                                                              

Use the EPR Vancomycin IV (Adult): Maintenance therapy - adjusting maintenance doses post levels PowerPlan. 

Select initial maintenance dose, dose interval and start time using the table below. Use Actual Body Weight and eGFR.

STEP 3. Select how often to monitor trough level 

• U+E’s should be monitored as determined by the patient’s clinical condition. 

STEP 4. How to interpret vancomycin trough level                                                                                           

• Target trough level is 15-20mg/L.
• Trough levels (pre-dose levels) only are monitored.
• Use the table below to interpret the trough level and if further action is needed.

NB: The maximum recommended IV dose is vancomycin 2g IV bd, if patient's trough level is sub-therapeutic despite being on 2g IV bd:

• Check and make sure this is a true trough level at 4^th maintenance dose or more.
• It is not usual to give more than 2g per dose. Therefore in patients who may require higher doses this is normally given by increasing the total daily dose and splitting this into 3 equal doses per day. This need to be discussed in conjunction with Micro/ID.

Applicable only for in-patients:

• With eGFR less than 20mL/min/1.73m²
• On peritoneal dialysis (PD)
• On acute haemodialysis or haemodiafiltration (patients whose dialysis requirements are changing on a daily basis) 
• Excludes:
  • Patients receiving continuous haemofiltration in critical care (see continuous vancomycin infusion guideline)
  • Patients who are receiving haemodialysis as an outpatient (separate unit guideline available)
  • Patients with PD peritonitis having intraperitoneal vancomycin (separate unit guideline available)

STEP 1. Select a loading dose                                                                                                                   

The following loading doses are recommended for all patients with eGFR less than 20mL/min/1.73m².

STEP 2. Check vancomycin level

Take a vancomycin level no more than 48 hours later. Take levels early in the day for result to be acted on the same day, as another dose of vancomycin may need to be prescribed. Target level is 15-20mg/L.

• If level is 20mg/L or less, prescribe a maintenance dose (see step 3).
• If level is greater than 20mg/L, do not give a dose and re-check level the following day.

STEP 3. Prescribe maintenance dose                                                                                                          

Maintenance doses are stated in the table below. The dose is once only and then re-check level (see step 2).

If having haemodialysis, prescribe dose to be given AFTER the dialysis session (alternatively, if intravenous access is an issue, the dose could be given towards the end of the dialysis session by the dialysis nurse – this must be discussed with renal team in advance).