Looking to order a test?
We’ve provided helpful links to make ordering easy.Find a Requisition
All specimens should be accompanied by a requisition.Submitting Specimens
Learn about how to properly label and where to ship specimens.Order Kits and Supplies
MLabs provides all the supplies necessary for the collection of specimens.Test FAQ
Visit our provider FAQ and learn about common questions to ordering tests.
Colorimetric (Xylidyl Blue)
To aid in assessing cellular magnesium loss
50 - 200 mg/24 hrs (5-20 mMol/24 hrs). Random urine collections are reported in units of mg/dL, for which reference values are not established.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
24 hour urine collection. Instruct patient to void at 8:00am (or 8:00pm) and discard the specimen. Then collect all the urine including the final specimen voided at the end of the 24 hour collection period, i.e., 8:00am (or 8:00pm) the following day. Transport promptly to the laboratory. Container must be labeled with date and time collection started and finished. Refrigerate during collection.
Collect 24 hour urine in a clean, plastic container with no metal cap or glued insert and no preservative. Aliquot 5 mL urine into a clean, plastic container with no metal cap or glued insert and refrigerate. Record total 24 hour urine volume and collection dates/times on request form. Random urine also acceptable.