Directions For Collecting A 24-Hour Urine Sample

Many members have asked about the proper way to collect a 24-hour urine. Here are the directions from one Porphyria laboratory. You might want to compare these directions with those from your own laboratory.

  1. Please use a dark plastic jug for collecting the urine. The urine should be protected from light during collection and during shipping. Add 5 grams of sodium carbonate, a powder that will readily dissolve in the urine, to the jug. This adjusts the acidity of the urine and helps preserve the substances the lab will be measuring. It is not toxic or irritating.

  2. A 24-hour urine collection must be started at a specific time and then ended at the same time the next day. You can choose any time that is convenient for you to start the collection. But you must also be sure that you can end the urine collection at the same time the next day.

  3. Record the time that you have chosen to start the collection. You need to start the urine collection with an empty bladder. Therefore, at exactly this time, empty your bladder and discard the urine. In other words, when you start the urine collection, you should empty your bladder and not add that urine to the jug.

  4. From that time on, add any urine that you pass to the jug. You do not need to record the time each time you urinate.

  5. During the collection, store the urine jug tightly capped in a refrigerator or place it in an ice chest.

  6. Exactly 24 hours after you start the urine collection, you should end the urine collection by emptying your bladder into the jug for the last time.

The University of Texas Medical Branch Porphyria Lab primer on testing for Porphyria is available here: http://pmch.utmb.edu/clinics-services/porphyria-center​