Vancomycin Trough Level
before you prescribe
- AUC dosing is the standard; not available here → troughs + pharmacy protocol
- check renal function, current dose and interval, time of the last dose
- serious infection? bacteremia, endocarditis, osteomyelitis, MRSA pneumonia
- renal risk → AKI / CKD, dehydration, sepsis, other nephrotoxins (aminoglycosides, NSAIDs, contrast, piperacillin-tazobactam)
- loading 25–30 mg/kg IV (actual weight) if serious or critical
- maintenance 15–20 mg/kg IV q8–12h, round to 250 mg, max 2 g/dose; q8h if young, burns, high clearance
- infuse over ≥ 1 h per gram
escalate now if
- sepsis or hemodynamic instability → fever, hypotension
- AKI or rising creatinine → hold and re-dose, acute kidney injury
- very high trough with worsening renal function → hold
- suspected vancomycin toxicity → is the trough real first, then pharmacy
when to draw the trough
- trough 30 min before the 4th dose (before the 3rd if interval ≥ 24 h), with creatinine
- not from the vancomycin line
- give the dose on time; don’t hold for the level unless AKI
what the number means
- standard → trough 10–15 mg/L
- deep-seated MRSA (bacteremia, endocarditis, osteomyelitis, meningitis, pneumonia): 15–20 mg/L
- 15–20 is not the same as AUC 400–600: it causes more AKI, use it only when the infection earns it
- a mistimed trough means nothing: repeat it before acting
adjusting the dose
- before changing anything → true trough (right time, right line)? doses given on time? creatinine changed?
- low → increase dose or shorten interval per pharmacy protocol; recheck before the 4th new dose
- high → hold, creatinine now, pharmacy re-doses; restart when back in range
- rising creatinine, trough repeatedly off, or infection not responding → pharmacy / ID
kidneys and side effects
- creatinine every 48–72 h; daily if unstable or on other nephrotoxins
- repeat trough after any dose change or creatinine change
- flushing / rash during infusion → slow to ≤ 500 mg/h, antihistamine; phlebitis → dilute more, slower, central line
- hand over → last trough + time, next level due, creatinine trend
evidence
| source | type |
|---|---|
| ASHP / IDSA / PIDS / SIDP Revised Consensus Guideline for Therapeutic Monitoring of Vancomycin (2020) | international guideline |
| AUC-guided monitoring not routinely available locally; trough-based monitoring is the practical workflow here | Kuwait local protocol |
Verify indication, dose, allergies, interactions, renal/hepatic function and local protocols before prescribing.
free the on-call checklist covers the whole shift on one printable page.
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reviewed Aug 2026updated Oct 2026file lab/vancomycin-trough-level