Voriconazole has non-linear kinetics and wide variation between patients, partly because of CYP2C19 genotype. The same dose can leave one patient underexposed and another toxic.
Check a trough level about five days into treatment, or sooner after a dose change or interacting drug. Low levels are linked to treatment failure; high levels to hepatotoxicity, visual disturbance, hallucinations and confusion. Review interactions too: voriconazole raises levels of many drugs, including tacrolimus, some statins and several anticancer agents.
- Check a voriconazole trough about five days after starting or changing the dose
- Recheck after starting or stopping an interacting drug
- Think of high levels in a patient with new confusion, hallucinations or visual change
- Review co-prescribed drugs — voriconazole raises levels of many
Why it matters
Fixed dosing misses both failure and toxicity in a drug this variable.
Read the rest in the app
You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.
Scan to keep reading on your phone. No account needed to start.
Tomorrow morning, before your first patient
One edition a day for infectious diseases, written by the desk, every claim tied to its paper. Six minutes.
Get the app — free