Drug of Abuse, Methadone Screen with GC-MS Confirmation, Urine
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Compliance monitoring of methadone therapy in patients being treated for heroin addiction
Reflex Tests Lists test(s) that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial test(s)
|Test ID||Reporting Name||Available Separately||Always Performed|
|MSMT||Drug of Abuse, Methadone Conf, U||Yes||No|
Testing Algorithm Delineates situation(s) when tests are added to the initial order. This includes reflex and additional tests.
If the methadone screen is > or =300 ng/mL then methadone confirmation is performed at an additional charge.
DMETH/505343: Enzyme-Multiplied Immunoassay Technique (EMIT)
MSMT/500372: Gas Chromatography-Mass Spectrometry (GC-MS)
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Drug of Abuse, Methadone, U
DAU Methadone Screen, Urine
Drugs of Abuse Methadone Screen, Urine
Methadone DAU Screen, Urine
Drugs of Abuse Methadone Screen, Urine
Methadone DAU Screen, Urine
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, 10-mL urine tube (Supply T068)
Specimen Volume: 10 mL
1. Collect a random urine specimen.
2. No preservative.
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 narcotic with analgesic and pharmacological properties similar to morphine. It can be administered orally and provides analgesia for approximately 24 hours. The I-racemate of the drug is active, while the d-racemate has little activity. Methadone has properties that make it useful for treating heroin addiction. Sedation ensues with higher doses, which is an undesirable side effect. Administered in small doses of 5 to 20 mg, the drug occupies the opioid receptor for prolonged periods of time, blocking the action of morphine, precluding the euphoric effect that heroin addicts seek. Addicts who self-administer heroin while taking methadone doses do not experience euphoria, only sedation, miosis, respiratory depression, hypotension, and dry-mouth. Tolerant patients may require doses up to 200 mg per day.
Methadone is metabolized by demethylation (cytochrome P  2D6 [CyP 2D6]) to 2-ethylidene-1, 5-dimethyl-3, 3diphenylpyrrolidine (EDDP) and to 2-ethyl-5-methyl-3, 3-diphenylpyrrolidine (EMDP). Individuals with genetic deficiencies of CyP 2D6 or coadministered amiodarone, paroxetine protease inhibitor antiretrovirals, chlorpheniramine, or other drugs that inhibit CyP 2D6 will accumulate methadone with associated toxicity.
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.
EMIT cutoff concentration: 300 ng/mL
Positives are reported with a quantitative GC-MS result.
A positive result derived by this testing indicates that the patient has used methadone in the recent past.
Because the urine output of methadone associated with minimal effective therapy can range between 1,000 to 50,000 ng/mL and only 5% is excreted unmetabolized, there is poor correlation of urine concentration with dose.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Goodman LS, Gillman A, Hardman JG, et al: The pharmacological basis of therapeutics. 9th edition. Edited by JG Hardman, LE Limbird. New York, McGraw Hill, 2001, pp 544-55
2. Baselt RC: In Disposition of Toxic Drugs and Chemicals in Man, 5th edition. Chemical Toxicology Institute, Foster City, CA 2000
Method Description Describes how the test is performed and provides a method-specific reference
Urine is preliminarily screened for the presence of methadone by immunoassay technique. If the result is positive by this technique, the urine is subjected to gas chromatography/mass spectrometry analysis. If a compound chromatograph where a methadone standard emerges with a mass spectrum consistent with that of a specific methadone drug, the presence of that methadone drug is confirmed. (Schwarzhoff RH, Hubster EC, Liserio MK: Enzyme immunoassay, kinetic microparticle immunoassay, radioimmunoassay, and fluorscence polarization immunoassay compared for drugs-of-abuse screening. Clin Chem 39:2137-2146, 1993; Foerster EH, Dempse J, Garriott JC: A gas chromatographic screening procedure for acid and neutral drugs in blood. J Anal Toxicol 3:87-91, 1979)
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 Friday, Sunday; Varies
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 has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
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.
83840-Confirmation (if appropriate)
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|