Methylphenidate and Metabolite, Random, Urine
Use
This test is useful for monitoring urine methylphenidate and ritalinic acid concentrations to assess compliance in patients undergoing treatment for attention-deficit hyperactivity disorder and narcolepsy. Methylphenidate works by blocking the reuptake of norepinephrine and dopamine into the presynaptic neuron, thus increasing their concentrations in the extraneural space. Monitoring allows healthcare providers to ensure proper dosing and adherence to medication regimens.
Special Instructions
If urine creatinine is required or adulteration of the sample is suspected, also order ADULT / Adulterants Survey, Random, Urine. STAT requests are not accepted for this test. If not ordering electronically, complete, print, and send a Therapeutics Test Request (T831) with the specimen.
Limitations
This test has not been cleared or approved by the US Food and Drug Administration. It has been developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. Only small quantities of unchanged methylphenidate appear in the urine, as most of the dose is excreted as ritalinic acid. Presence of these substances indicates the patient has taken methylphenidate in the past 1 to 2 days. Improper specimen collection and handling, inappropriate test selection, and interfering substances could impact results.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 104676-2
- 20548-4
- 72790-9
- 69050-3
Result Turnaround Time
2-4 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
5 mL
Minimum Volume
0.5 mL
Container
Plastic, 5-mL tube
Collection Instructions
Collect a random urine specimen. No preservative. No specimen substitutions. Submitting less than 1 mL will compromise all necessary testing.
Causes for Rejection
None specified; Gross hemolysis and gross icterus are acceptable.
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 10 days |
| Frozen | 28 days |