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12-hour urine test (boric acid)

Your doctor has requested that you have a test on a urine sample collected over 12 hours/overnight with a boric acid additive.

The bottle you have been given contains boric acid. Do not discard this as it is used as a preservative.

Safety precautions—boric acid additive

  • This bottle contains 8g of boric acid, which acts as a preservative.
  • If the boric acid comes into contact with your skin or clothing wash the area thoroughly with water.
  • If poisoning occurs, contact a doctor or the Poison Information Centre (13 11 26).
  • Keep out of reach of children.

Collecting your sample

It is important that the sample is a complete 12-hour/overnight collection and it is recommended that you start the collection process in the evening. Should you forget to use the bottle during the collection period, you will need to restart the collection with a new bottle from the laboratory. Contact the collection centre for advice if you cannot complete the collection for any reason.

  1. Label the collection bottle provided with your full name and date of birth.
  2. At the beginning of the collection, empty your bladder completely into the toilet and mark the time (e.g. 8pm) in the space provided on the collection bottle.
  3. Over the next 12 hours or overnight, collect all of your urine into the bottle. Each time you add urine to the bottle, mix gently with the boric acid—avoid contact with the skin.
  4. The last collection should be as near as possible to 12 hours after the first discarded specimen on day one, and should include the urine you pass first thing on day two. Make sure that the start and finish date and time are clearly marked on the bottle.
  5. Place the request slip into the biohazard bag and attach the bag to the collection bottle—do not place over the label.
  6. Keep the collection bottle in a cool place during the collection period—refrigerate if possible. Return it to the collection centre on the morning you finish the collection.

If you have any questions please contact your preferred collection centre or your referring doctor.

Need more information?

Urinalysis: chemical examination at Lab Tests online.

QIS document number: 28373

Last updated: 1 September 2020