Methadone and Metabolite, Serum or Plasma, Quantitative
Also known as: METHADO SP
Use
This test is used to monitor patient adherence to methadone therapy. It quantitatively measures methadone and its primary metabolite, EDDP, in serum or plasma. Monitoring methadone levels can help assess compliance, absorption, and appropriate timing of specimen collection relative to drug administration. It is intended for medical purposes only and not valid for forensic use.
Special Instructions
Separate serum or plasma from cells as soon as possible or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP standard transport tube. Use gray (sodium fluoride/potassium oxalate) tubes, or alternatively plain red, green (sodium heparin), lavender (EDTA), or pink (K2EDTA) tubes. Refrigerate specimens for storage/transport. Avoid separator tubes, plasma or whole blood collected in sodium citrate, or specimens exposed to repeated freeze/thaw cycles.
Limitations
The absence of expected drug(s) and/or drug metabolite(s) may indicate non-compliance, inappropriate timing of specimen collection relative to drug administration, poor drug absorption, or limitations of testing. The concentration value must be greater than or equal to the cutoff to be reported as positive. Interpretive questions should be directed to the laboratory.
New York Approved
Methodology
Mass Spectrometry
Biomarkers
LOINC Codes
- 3772-1
- 60071-8
- 3772-1
- 60071-8
Result Turnaround Time
1-7 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
ARUP standard transport tube
Collection Instructions
Separate serum or plasma from cells as soon as possible or within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP standard transport tube.
Storage Instructions
Refrigerated.
Causes for Rejection
Separator tubes. Plasma or whole blood collected in lt. blue (sodium citrate). Specimens exposed to repeated freeze/thaw cycles. Hemolyzed specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 1 week |
| Refrigerated | 2 weeks |
| Frozen | 3 years |