MEPHENYTOIN (MESANTOIN®) AND NORMEPHENYTOIN, PLASMA OR SERUM
Reporting Title: Mephenytoin (Mesantoin)
Methodology: High Performance Liquid Chromatography with Ultraviolet
Detection (HPLC-UV)
	Test Performed At:
		MedTox Laboratories through Mayo Medical Laboratories #90519
	Specimen Required:
		Collect 5.0 mL (minimum 1.0 mL) of whole blood in a plain, red-top tube(s). (SERUM GEL TUBE IS NOT ACCEPTABLE.)
		NOTE:		Trough levels are most reproducible.
				Submission of the minimum volume results in an elevated reporting limit and inability to repeat analysis.
	Laboratory Notes:
		Spin, separate and send 2.0 mL (minimum 0.5 mL) of serum refrigerated in a 5 mL screw-cap vial.
		NOTE:		1.	Will also accept heparinized plasma.
				2.	If plasma is specimen type sent, comment ‘plasma’ on aliquot vial.
				3.	Submission of minimum volume results in an elevated reporting limit and inability to repeat analysis.
				4.	Order test in MayoAccess and note MedTox test code 1450
	Reference Values:
		MEPHENYTOIN
			Reporting limit:			0.5 mcg/mL
			Reference range:			1.0-5.0 mcg/mL
			Critical value:			20.0 mcg/mL
		NORMEPHENYTOIN
			Reporting limit:			1.0 mcg/mL
			Reference range:			15.0-35.0 mcg/mL
			Critical value:			50.0 mcg/mL
	Day(s) Test Set Up:
		Monday - Sunday
	Cut-Off Time:
	Turn Around Time:
		5-7 days
	CPT Code:
		82492
	Care Manager Order Name:
		Mephenytoin (Mesantoin) ONCE RTN
	KIDDOS Order Name:
		Mephenytoin Level
	Cerner Order Name:
		Mephenytoin

Last Updated 10/09