Test Catalog

Test Id : MPHNU

Methylphenidate and Metabolite, Random, Urine

Useful For
Suggests clinical disorders or settings where the test may be helpful

Monitoring urine methylphenidate and ritalinic acid concentrations to assess compliance in patients

Method Name
A short description of the method used to perform the test

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Methylphenidate and Metabolite, U

Lists additional common names for a test, as an aid in searching






Specimen Type
Describes the specimen type validated for testing


Additional Testing Requirements

If urine creatinine is required or adulteration of the sample is suspected, also order ADULT / Adulterants Survey, Random, Urine. For more information, see ADULT / Adulterants Survey, Random, Urine.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Supplies: Sarstedt 5 mL Aliquot Tube (T914)

Collection Container/Tube: Plastic urine container

Submission Container/Tube: Plastic, 5-mL tube

Specimen Volume: 5 mL

Collection Instructions:

1. Collect a random urine specimen.

2. No preservative.

Additional Information:

1. No specimen substitutions.

2. STATS are not accepted for this test.


Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

1 mL

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

Gross hemolysis OK
Gross icterus OK

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 10 days
Frozen 28 days

Useful For
Suggests clinical disorders or settings where the test may be helpful

Monitoring urine methylphenidate and ritalinic acid concentrations to assess compliance in patients

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Methylphenidate (MPH) is utilized for the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. MPH has two chiral centers and is marketed as a racemic mixture and as the active d-enantiomer of racemic methylphenidate. Although the exact mechanism of its action has not been fully defined, it blocks the reuptake of norepinephrine and dopamine into the presynaptic neuron thus increasing the concentrations of these monoamines in the extraneural space. Methylphenidate is extensively metabolized to ritalinic acid, which is an inactive metabolite.

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.



Cutoff concentrations:

Methylphenidate by LC-MS/MS: 10 ng/mL

Ritalinic Acid by LC-MS/MS: 50 ng/mL

Provides information to assist in interpretation of the test results

Methylphenidate has an oral bioavailability of 22% to 100% with peak concentrations occurring around 2 hours for instant release and approximately 5 to 6 hours for extended release formulations. The half-life of methylphenidate is 2 to 4 hours. Methylphenidate is extensively metabolized to ritalinic acid, which is an inactive metabolite. The half-life of ritalinic acid is about 3 to 4 hours. Only small quantities (<1%) of unchanged methylphenidate appear in the urine as most of the dose (60%-86%) is excreted in the urine as ritalinic acid. The presence of methylphenidate or ritalinic acid in the urine indicates the patient has taken methylphenidate in the past 1 to 2 days.

Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

No significant cautionary statements.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1 .Kimko HC, Cross JT, Abernethy DR: Pharmacokinetics and clinical effectiveness of methylphenidate. Clin Pharmacokinetics. 1999 Dec;37(6):457-470. doi: 10.2165/00003088-199937060-00002

2. Ramos L, Bakhtiar R, Tse FL: Liquid-liquid extraction using 96-well plate format in conjunction with liquid chromatography/tandem mass spectrometry for quantitative determination of methylphenidate (Ritalin1) in human plasma. Rapid Commun Mass Spectrom. 2000;14(9): 740-745. doi: 10.1002/(SICI)1097-0231(20000515)14:9<740:AID-RCM938>3.0.CO;2-C

3. Paterson SM, Moore GA, Florkowski CM, George PM: Determination of methylphenidate and its metabolite in urine by liquid chromatography/tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci. 2012 Jan 15;881-881:20-26. doi: 10.1016/j.jchromb.2011.11.007

4. Mulet CT, Arroyo-Moro LE, Leon LA, Gnagy E, DeCaprio AP: Rapid quantitative analysis of methlylphenidate and ritalinic acid in oral fluid by liquid chromatography triple quadrupole mass spectrometry. JChromatogr B Analyt Technol Biomed Life Sci. 2018 Aug 15;1092:313-319. doi: 10.1016/j.jchromb.2018.06.025

5. Langman LJ, Bechtel LK, Meier BM, Holstege C: Clinical toxicology. In: Rifai N, Horvath AR, Wittwer CT, eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Elsevier; 2018:1323-1324

Method Description
Describes how the test is performed and provides a method-specific reference

The urine sample is centrifuged, diluted with internal standard and clinical laboratory reagent water, and then analyzed by liquid chromatography-tandem mass spectrometry.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday, Wednesday, Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

2 to 4 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

14 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test


Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their account representative. For assistance, contact Customer Service.

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 instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) 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 US 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 Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


G0480 (if appropriate)


LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
MPHNU Methylphenidate and Metabolite, U In Process
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
608882 Methylphenidate by LC-MS/MS 20548-4
608883 Ritalinic Acid by LC-MS/MS 72790-9
608884 Methylphenidate Interpretation 69050-3

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports

Test Update Resources

Change Type Effective Date
New Test 2021-05-11