Test directory: Methotrexate

Ordering Code 751
Test Name Methotrexate
Alias Mexate
Preferred Specimen Serum
Preferred Container Plain (Red)
Collection Instructions Clot red top tube for 45 minutes, aliquot & foil aliquot tube immediately to protect from light
Refrigerate specimen within 4 hours of collection.
Handling Instructions Centrifuge to separate within 1 hour of collection. Aliquot and foil aliquot tube immediately to protect from light
Refrigerate specimen within 4 hours of collection.
Transport Requirements Oahu: Refrigerated
Airline: Frozen
Specimen Stability Ambient: 4 Hours
Refrigerated: 2 Weeks
Frozen: Indefinite
Rejection Criteria Specimen older than stability limits, Grossly hemolyzed,
Not protected from light, SST tube
Avail. Stat NO
Analytic Time 1 Day
Methodology Enzyme Immunoassay (EIA)
Reference Lab  Clinical Labs of Hawaii - KMCWC

Reference range(s)

The reference ranges listed below are valid on this date of June 29, 2025.
Component Age Male Norm Male Critical Low Male Critical High Female Norm Female Critical High Female Critical Low Units Add'l info
Methotrexate ALL uM/L See report.
Methotrexate, Exp ALL M/L

Interpretation...
Interpretation:
No precise relationship between methotrexate serum levels and antineoplastic efficacy has been established, although levels below approximately 0.02 uM/L were seen as necessary for resumption of DNA synthesis

Critical methotrexate levels vary depending upon the dose delivered and the length of infusion. Consult individual treatment protocols to determine if hydration or leucovorin rescue should be changed

Testing has been performed by
Clinical Laboratories of Hawaii
Kapiolani Medical Center 1319 Punahou Street
Honolulu, HI 96826
See report.
Note1

Note1:


Interpretation:
No precise relationship between methotrexate serum levels and antineoplastic efficacy has been established, although levels below approximately 0.02 uM/L were seen as necessary for resumption of DNA synthesis

Critical methotrexate levels vary depending upon the dose delivered and the length of infusion. Consult individual treatment protocols to determine if hydration or leucovorin rescue should be changed

Testing has been performed by
Clinical Laboratories of Hawaii
Kapiolani Medical Center 1319 Punahou Street
Honolulu, HI 96826
See report..