91164      Methotrexate
Specimen:
  Collect: One 10 mL Red Top

Also Acceptable
One 4 mL Lavender (EDTA)
One 4 mL Green Top (Li Heparin)
One 4 mL Gray Top
One 6 mL Pink Top (EDTA)
One 4 mL Green Top (Na Heparin) 
  Submit: 3 mL (Min:1 mL) Serum. Submit Frozen. Submit in a Standard Transport Tube.

Also Acceptable
3 mL (Min:1 mL) Plasma. Submit Frozen. Submit in a Standard Transport Tube. 
  Special Handling: Protect from Light
Separate aliquot required for each frozen test ordered
Separate from cells ASAP
Protect from light during collection, storage, and shipment. Separate serum from cells within 2 hours of collection.  
  Rejection Criteria: Use of gels
Use of separator tubes 
  Stability: Ambient: 4 Hour(s); Refrigerated: 24 Hour(s); Frozen: 6 Month(s); Incubated: Unacceptable 
Methodology: Enzyme Immunoassay (EIA) 
Performed: Sun-Sat 
Reported: 1-2 Day(s) 
CPT Codes:
80299
Interpretive Data:
General Reference Range : 0.50-1.00 umol/L