Guidelines
Flucytosine - Monitoring

Flucytosine - Monitoring

Neonatal Monitoring

CBC with differential, electrolytes, urea, creatinine, liver function tests (ALT, AST) before therapy and twice weekly

Neonatal Therapeutic Drug Monitoring

When ordering levels first call either of the following to obtain authorization to do levels.

  • Calvin Lee ([email protected] (Ext 3123) Team Lead, Clinical biochemistry
  • Dr. Benjamin Jung ([email protected]) (Ext: 2453) Division Head, Clinical Biochemistry
  • All fluctytosine levels are sent to the Mayo Clinic in Rochester, Minnesota, USA, for processing.
  • The turn around time for levels is 7 days.
  • When filling out the lab requisition write “Flucytosine Drug Level (to Mayo Clinic, USA)” on requisition.
  • Mayo Clinic requires 2 mL of blood per level.
  • If the beside nurse collects the blood use red top tubes.
  • Please note that one of the parents must complete and sign a consent form for release of information. The consent form should be sent back to the lab with the Flucytosine requisition.

Peak Level: 50-100 mg/L drawn 30 minutes after completion of a 30 minute IV infusion

Trough level: 25-50 mg/L

For IV Administration: Obtain Peak and trough levels after third dose when starting treatment and after every change in dose.

For Oral Administration: Obtain trough level prior to the third dose when starting treatment and after every change in dose.