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Test Code KETAU Ketamine and Metabolite Confirmation, Urine

Performing Laboratory

Mayo Medical Laboratories in Rochester

Reporting Name

Ketamine Confirmation, U

Specimen Type


Specimen Required

Container/Tube: Plastic, 60-mL urine bottle

Specimen Volume: 20 mL

Collection Instructions:

1. Collect a random urine specimen.

2. No preservative.

Additional Information:

1. No specimen substitutions.

2. No STATS are accepted for this procedure.

3. For situations where chain of custody is required, a Chain-of-Custody Kit (T282) is available. For chain-of-custody testing, order KETAX / Ketamine Confirmation, Chain of Custody, Urine.

4. Additional drug panels and specific requests are available. Call Mayo Medical Laboratories at 800-533-1710 or 507-266-5700.

5. If urine creatinine is required or adulteration of the sample is suspected, the following test should be requested, ADULT / Adulterants Survey, Urine. For additional information, refer to ADULT / Adulterants Survey, Urine.

6. Submitting <20 mL will compromise our ability to perform all necessary testing.

Reject Due To









Specimen Stability Information

Specimen Type Temperature Time
Urine Refrigerated (preferred) 14 days
  Frozen  14 days
  Ambient  72 hours

Specimen Minimum Volume

5 mL

Day(s) and Time(s) Performed


Specimen Retention Time

2 weeks

Analytic Time

2 days

Reference Values


Useful For

Detection and confirmation of ketamine use

Method Name

Gas Chromatography-Mass Spectrometry (GC-MS)

Test Classification

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


G0480 (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
KETAU Ketamine Confirmation, U In Process


Result ID Test Result Name Result LOINC Value
31128 Norketamine 18322-8
89443 Ketamine Confirmation, U 20537-7
29903 Ketamine Interpretation 69050-3
29904 Chain of Custody No LOINC Needed

Clinical Information

Ketamine has been used in the United States as an anesthetic induction agent since 1972. The drug acts by noncompetitive antagonism of the N-methyl-D-aspartate (NMDA)-type glutamate receptors.(1,2) Ketamine has become a popular street drug because of its hallucinogenic effects.(3)


Ketamine has a half-life of 3 to 4 hours, and is metabolized to norketamine.(3) The effects from ketamine last from 1 to 5 hours, and ketamine and/or norketamine can be detected in the urine for a period of 1 to 2 days following use.(4)


The presence of ketamine and/or norketamine >25 ng/mL is a strong indicator that the patient has used ketamine.


A kit including all the materials necessary to complete chain-of-custody is available to ensure that the test results are appropriate for legal proceedings.

Clinical Reference

1. Ujhelyi MR, Robert S, Cummings DM, et al: Influence of digoxin immune Fab therapy and renal dysfunction on the disposition of total and free digoxin. Ann Intern Med 1993;119:273-277

2. Goodman and Gilman's: The Pharmacological Basis of Therapeutics. 10th edition. New York. McGraw-Hill Book Company, 2001

3. Baselt RC. Disposition of Toxic Drugs and Chemicals in Man. Seventh edition. Foster City, CA. Biomedical Publications, 2004 pp 1254

4. Mozayani A: Ketamine-Effects on human performance and behavior. Forensic Sci Rev 2002;14:123-131

Method Description

Phencyclidine, norketamine, and ketamine, along with the deuterated internal standards, are extracted from buffered urine using solid-phase extraction techniques. The eluent from the column is dried and then analyzed by gas chromatography-mass spectrometry.(Unpublished Mayo method)