Asked by: Ben Warwick, Poole
The bladder holds 400-600ml of urine. Normal urine production is around 1.5 litres every 24 hours, so that would give you nine or 10 hours to completely fill up.
However you can drop to as little as 400ml of urine production a day for short periods without suffering harmful consequences. This could conceivably give you as long as 36 hours between trips to the loo.