Methadone Confirmation, Urine
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Monitoring of methadone treatment for analgesia or drug rehabilitation
Urine measurement of 2-ethylidene-1,5-dimethyl1-3,3-diphenylpyrrolidine is particularly useful for assessing compliance with rehabilitation programs.
Additional Tests Lists test(s) that are always performed, at an additional charge, with the initial test(s)
|Test ID||Reporting Name||Available Separately||Always Performed|
|ADULT||Adulterants Survey, U||No||Yes|
Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.
An evaluation to detect the presence of adulterants will be performed and reported at no additional charge.
See Adulterant Survey Algorithm in Special Instructions.
Special Instructions and Forms Describes specimen collection and preparation information, test algorithms, and other information pertinent to test. Also includes pertinent information and consent forms to be used when requesting a particular test
MTDNU/83129: Immunoassay/Gas Chromatography-Mass Spectrometry (GC-MS) Confirmation with Quantitation
ADULT/29345: Spectrophotometry (SP)
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Methadone Confirmation, U
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Container/Tube: Plastic, 60-mL urine bottle
Specimen Volume: 20 mL
1. Collect a random urine specimen.
2. No preservative.
1. For situations where chain-of-custody is required, a Chain-of-Custody Kit (Supply T282) is available. For chain-of-custody information, see COCH/9426 Chain-of-Custody Processing.
2. Additional drug panels and specific requests are available. Call Mayo Medical Laboratories at 800-533-1710 or 507-266-5700.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Urine||Refrigerated (preferred)||14 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Methadone (Dolophine) is a synthetic opioid, a compound that is structurally unrelated to the natural opiates but is capable of binding to opioid receptors. These receptor interactions create many of the same effects seen with natural opiates, including analgesia and sedation. However, methadone does not produce feelings of euphoria and has substantially fewer withdrawal symptoms than opiates such as heroin.(1) Methadone is used clinically to relieve pain, to treat opioid abstinence syndrome, and to treat heroin addiction in the attempt to wean patients from illicit drug use.
Metabolism of methadone to inactive forms is the main form of elimination. Oral delivery of methadone makes it subject to first-pass metabolism by the liver and creates interindividual variability in its bioavailability, which ranges from 80% to 95%. The most important enzymes in methadone metabolism are CYP3A4 and CYP2B6.(1-4) CYP2D6 appears to have a minor role, and CYP1A2 may possibly be involved.(1-5) Methadone is metabolized to a variety of metabolites, the primary metabolite is 2-ethylidene-1,5-dimethyl1-3,3-diphenylpyrrolidine (EDDP).(1-4) The efficiency of this process is prone to wide inter- and intraindividual variability, due both to inherent differences in enzymatic activity as well as enzyme induction or inhibition by numerous drugs. Excretion of methadone and its metabolites (including EDDP) occurs primarily through the kidneys.(1,4)
Patients who are taking methadone for therapeutic purposes excrete both parent methadone and EDDP in their urine. Clinically, it is important to measure levels of both methadone and EDDP. Methadone levels in urine vary widely depending on factors such as dose, metabolism, and urine pH.(5) EDDP levels, in contrast, are relatively unaffected by the influence of pH and are, therefore, preferable for assessing compliance with therapy.(5)
Some patients undergoing treatment with methadone have attempted to pass compliance testing by adding a portion of the supplied methadone to the urine.(7) This is commonly referred to as "spiking.'' In these situations the specimen will contain large amounts of methadone and no or very small amounts of EDDP.(7) The absence of EDDP in the presence of methadone in urine strongly suggests adulteration of the urine specimen by direct addition of methadone to the specimen.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Positives are reported with a quantitative GC-MS result.
METHADONE BY GC-MS
2-ETHYLIDENE-1,5-DIMETHYL-3,3-DIPHENYLPYRROLIDINE BY GC-MS
The absolute concentration of methadone and its metabolites found in patient urine specimen can be highly variable and do not correlate with dose. However, the medical literature and our experience show that patients who are known to be compliant with their methadone therapy have ratios of 2-ethylidene-1,5-dimethyl1-3,3-diphenylpyrrolidine (EDDP):methadone of >0.60.(6)
An EDDP:methadone ratio <0.090 strongly suggests manipulation of the urine specimen by direct addition of methadone to the specimen.(7)
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Urine pH has a considerable effect on the ability to detect methadone, thus 2-ethylidene-1,5-dimethyl1-3,3-diphenylpyrrolidine is preferable for urine measurements.
Urine concentrations of methadone show very poor correlation to serum levels or the amount of drug administered.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Chapter 23: Opioid analgesics. In Goodman and Gilman's: The Pharmacological Basis of Therapeutics. 10th edition. Edited by HB Gutstein, H Akil. McGraw-Hill Book Company, 2001, pp 569-619
2. Eap CB, Buclin T, Baumann P: Interindividual variability of the clinical pharmacokinetics of methadone: implications for the treatment of opioid dependence. Clin Pharmacokinet 2002;41:1153-1193
3. Ferrari A, Coccia CP, Bertolini A, Sternieri E: Methadone-metabolism, pharmacokinetics and interactions. Pharmacol Res 2004;50:551-559
4. Baselt RC: Disposition of Toxic Drugs and Chemicals in Man. Seventh edition. Foster City, CA, Chemical Toxicology Institute, 2005
5. Principles of Forensic Toxicology. Second edition. Washington DC, AACC Press, 2003, pp 385
6. George S, Braithwaite RA: A pilot study to determine the usefulness of the urinary excretion of methadone and its primary metabolite (EDDP) as potential markers of compliance in methadone detoxification programs. J Anal Toxicol 1999;23:81-85
7. Galloway FR, Bellet NF: Methadone conversion to EDDP during GC-MS analysis of urine samples. J Anal Toxicol 1999;23:615-619
Method Description Describes how the test is performed and provides a method-specific reference
Screening is done by immunoassay technique. Positive screening results are confirmed by gas chromatography-mass spectrometry (GC-MS), solid phase extraction.(Unpublished Mayo method)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Thursday, Sunday
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|21110||Chain of Custody||In Process|