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Collecting a 24-hour urine specimen

Your doctor has requested some tests that require the collection of a 24-hour urine sample. It is important that this is done as described below so that the correct results are obtained.

You have been given a bottle(s) in which to collect your urine. Please make sure:

  1. Your NAME, Date of Birth, START and FINISH date and times of the urine collection are recorded on the container.
  2. On the day of the collection, pass the first urine of the day in the usual way. Please do not collect this first urine in the container.
  3. After this, collect ALL the urine passed in the next 24 hours into the container provided.
  4. At the end of the 24-hour period, this last urine sample must also be collected into the container.
  5. Your 24-hour urine collection is now complete.
  6. Bring the urine collection, together with the request form from your doctor; to the Pathology Laboratory at Stoke Mandeville Hospital or Wycombe Hospital as soon as possible (preferably on the day you finish the collection).

Pathology laboratory opening times:

Mon – Fri:                9am-5pm
Sat/Sun:                  Closed
Bank Holiday:          Closed

If you have any queries about how to collect the urine, please call the laboratory team on 01494 425398 or 01296 315354 (direct line).

Please note:

The test will be invalid if you forget to collect any urine you pass during the 24-hour collection, so if this happens, you will have to discard the whole collection and start again.

You may be given 2 containers for a single 24-hour collection. This is to ensure that if the first bottle is filled up, any extra urine may be collected in the second container to ensure a complete collection.

If the second bottle is not used, please bring this back to the Pathology Lab along with the full collection.

If your request form is for ‘Creatinine Clearance’, you will also need to have a blood sample taken in a yellow top tube.  If you have not had a blood test 1-2 days before your urine collection, please inform your GP to arrange this.

If collecting a 24-hour urine specimen for a urine 5HIAA test:

Foods and Drugs to avoid when collecting 24 hr urine sample for 5HIAA and Catecholamines

Certain foods and medications interfere with the 5HIAA urine tests, so it is important that you avoid the following 3 days before you start collecting the urine and also during the urine collection. You may need to discuss your current medication with your doctor in case you require alternatives.

  • Foods to avoid:
    bananas, plantains, aubergines, avocados, red plums, pineapple, kiwi fruit, walnuts, hickory nuts, pecan nuts, chocolate, coffee, broccoli, tomatoes, alcohol, vanilla, and health food supplements containing 5-hydroxytrytophan.
  • Medications to avoid:

anti-rheumatoid drugs, methyl dopa, diazepam, mephensin, β-blockers (blood pressure pill) and cold remedies.


Please wrap the 24-hour container in tin foil or a brown paper bag as the sample needs to be protected from light throughout.

Then follow the urine collection instructions as detailed above.