Adult patient:
EDTA tube
Minimum blood volume: 3 mL
Paediatric EDTA tube
Number of vials: 1
Minimum blood volume: 1.3 mL
Authorisation code required
No
24 Hr available service
No
Method
Liquid chromatography-tandem mass spectrometry
Reference interval
Target trough concentration (µg/L):
| Post-Tx (months) | Kidney | Liver |
| 0 - 3 | 10 - 15 | - |
| 3 - 12 | 5 - 15 | - |
| > 12 | 5 - 10 | - |
| 0 - 1 | - | 10 - 20 |
| 1 - 3 | - | 5 - 15 |
| > 3 | - | 5 - 10 |
(Source: Ther Drug Monit 2009; 31: 139 - 152)
Clinical indication
Therapeutic drug monitoring in patients receiving tacrolimus (FK506) therapy to avoid rejection of organ transplants and to detect toxic levels.
Result interpretation
An elevated result provides an early indication of the possibility of toxicity.
Measurement of uncertainty
Frequency of measurement
Twice weekly