Methadone, Serum or Plasma
Also known as: Dolophine®, Methadose®
Use
Therapeutic monitoring of methadone (Dolphine®/Methadose®) treatment.
Special Instructions
For therapeutic monitoring purposes only. Ensure accurate dosage adjustments and monitor patient response. Avoid use of gel-barrier tubes due to possible drug absorption which might clinically misrepresent drug levels.
Limitations
Methadone detection occurs 15 to 45 minutes post-oral administration, with peak levels at 2.5 to 4 hours; its elimination half-life averages around 22 hours (ranging from 5 to 130 hours). Significant inter-individual variability exists due to differences in P450 enzyme systems, leading to a potential 17-fold variation in blood concentrations among patients receiving the same dose. As this test is not FDA cleared, healthcare providers should interpret results with caution.
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 3772-1
- 3772-1
Result Turnaround Time
3-6 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
0.3 mL
Container
Red-top tube, lavender-top (EDTA) tube, or green-top (heparin) tube.
Collection Instructions
Transfer separated serum or plasma to a plastic transport tube.
Storage Instructions
Store at room temperature.
Causes for Rejection
Gel-barrier tube
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |