Doctors are worried a mandatory reporting system aimed at making roads safer could be achieving the opposite effect.

In South Australia, doctors are obliged to report patients who are suffering from sleep apnoea who might be a risk to other drivers or themselves.

Sometimes this results in the patient having their licence taken away.

Sleep apnoea is a disorder where the soft tissue at the back of the throat cuts off the air flow during sleep.

Studies suggest one in four South Australian men suffers from the condition which, in its extreme form, can leave the patient so exhausted during the day they suffer from involuntary naps or blackouts.

One sufferer Troy Seyfang said the condition disrupted his sleep hundreds of time each night and that led to ramifications in his waking hours.

"You couldn't go out and socialise, for instance couldn't go to movies because you'd be sitting there going to sleep, it was just impossible," he said.

"At work you’d be sitting at a computer having micro-second noddies and I absolutely dreaded [meetings] because you'd turn up and virtually slap yourself in the face and say 'please don't fall asleep'."

Change of onus urged

Doctors treating sleep apnoea understand why they must report patients to authorities, due to the risk of road accidents.

There is no specific data on accidents caused by sleep apnoea, but studies attribute 10 per cent of road crashes to people's medical conditions.

No one is arguing about the logic of the law, but the president of the Australasian Sleep Association, Nick Antic, believes it is achieving a reverse effect, with patients not reporting their condition to doctors for fear it could lead to a loss of their driver's licence.

"Those sorts of people are out there and they are untreated at the moment and some of them are probably very sleepy and some of them are at risk on the roads," he said.

"They are not having a treatable medical condition treated because of this perceived threat and I don't think that is good for South Australia."

Medical professionals say they have been threatened by people who are fearful of losing their licences and livelihoods.

Sorry, this video has expired Response from Deputy Registrar of Motor Vehicles Tim Harker

Associate Professor Antic said he needed a security guard with him in the consulting room while treating one patient.

"It was a very unpleasant environment and entirely unproductive to providing health care to people," he said.

Doctors argue the law needs to change so the responsibility for reporting to the licensing authority is put on the driver, leaving doctors to get on with their job of managing patients.