Methotrexate

Tube Type

Test ID

LAB481

EPIC Order

METHOTREXATE

CPT Code(s)

80204

Group/Individual Test

Individual

Laboratory

Core Laboratory

Tube Station

Routine: 30; STAT: 888

Specimen

Routine:

2 mL blood/navy blue plain tube or red plain tube (no gel)

Micro:

500 µL blood/red top (no gel) or red top pediatric bullet; See Comments

Stability

Unspun: 2 hours

Spun & Separated Room temperature: 2 hrs

Spun & Separated Refrigerator: 14 days

Spun & Separated Frozen: 6 months

Availability

24 hrs/day

Turnaround Time

Routine: 2 hours; STAT: 1 hour.

Reference Range

Therapeutic:

See Table below

Toxic:

See Table below

Comments

High-dose Therapy--Collect samples at 24, 48, or 72 hours after high dose infusion. Order Methotrexate Level, Pediatric High Dose [LAB5355] to initiate dilution protocols in the lab.
Low-dose Therapy--Collect samples 0.5 hr after IV low dose or 2 hr after PO dosing.

Reference Ranges: Methotrexate

Collection Time (Hrs. post dose.)	Therapeutic (µm/L)*	Toxic (µm/L)
24	<10.0	>10.0
48	<1.0	>1.0
72	<0.1	>0.1
	* Dependent upon malignancy and treatment protocol.

NOTE: Patients who have received Glucarpidase should not be monitored using this assay due to cross-reactivity. Call Referral Testing at (984) 974-1414 for further information regarding an alternate method.

Reviewed by J. Carr on January 13, 2026

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514