For most people, using a toilet away from home is something done with, at worst, irritation - we all cringe when we come across dirty, damaged facilities; yet for a surprisingly large group of people, to use any toilet away from home causes anything from mild anxiety to full-blown panic, no matter what state of cleanliness and upkeep…and that's if they can even manage to "go" when they get there.

It is estimated that in the region of 30% of the population will find this happening to them at one time or another, but it can also become a long-term problem. For some people trying to urinate when others are present, or just nearby, can stop them being able to urinate at all and others may be unable to urinate at home even, if others are present. For some sufferers the sight of another person in close proximity will hinder urination (say at a urinal,) for others, the sound made by their urine, and the possibility of this being heard by others is the trigger for stress and inability to urinate.

There is growing recognition of the condition by the NHS and Government. The condition is catered for in the rules for mandatory urine testing for drugs in UK prisons, and UK incapacity benefit tribunals also recognise it. It is scheduled to be included in the NHS on-line directory of conditions and disorders and is now reported to have been accepted as a valid reason for jury service excusal

This problem falls into two categories, firstly those for whom stress is brought on by being in a strange environment, at a strange loo for example. The second category of sufferer may have a phobia known as Shy Bladder or Shy Pee.

Shy Bladder Syndrome is also known as Avoidant Paruresis, it is a social phobia and involves difficulty or inability to urinate when in the presence of others (or when others are thought to be nearby.) It stems from a fear of being judged, of being "on the spot."

Sufferers will often go to great lengths to identify "safe" toilets, say in workplaces or social settings, working out the route to these toilets and perhaps including contingency plans for an "emergency" situation. This preoccupation and the resultant anxiety can affect every part of their work, family and social life.

Physical harm may result from not emptying a full bladder - and yet the sufferer wants to urinate, knows they should, but is physically unable to do so. This is not someone "holding it in" until they find a better environment, a cleaner loo for example (although this case might be the early stages of the condition.)

Restricting liquid intake is often used as a way to avoid the problem, as is the use of catheters, however neither solution is healthy as a long-term solution, and they completely avoid the source of the anxiety.

Whilst some sufferers report feeling no particular symptoms of anxiety whilst being unable to urinate, others report physical symptoms such as heart palpitations, sweating, dizziness, faintness and shaking..

From 1st August 2005, the guidance on the rules relating to the testing of those on probation in the UK, explicitly cites paruresis as a valid reason for inability to produce a sample (which is not to be construed as a refusal.)