Talia Jade Van-Rysewyk was absent from Kiama Local Court on Monday after faxing through a medical certificate claiming she was unfit to attend.

Defence solicitor Renata Matyear requested an adjournment on the 24-year-old's behalf, telling the court her client had been struck down by a vomiting bug.

Unimpressed by the vague medical certificate and explanation, the magistrate, Mark Richardson, requested that the doctor who issued the certificate give evidence in court.

"I can't be running a court on the basis that she gets up in the morning and feels crook," the magistrate said.

"Is she in hospital? Can she walk? Can she speak? [The certificate doesn't say.]"

Wollongong Medical Centre GP Dr Aidan Lawrence told the court he issued the certificate after seeing Van-Rysewyk at 8.23am on Monday morning.

"She basically has an acute infective illness ... it's likely to be contagious," he said via speakerphone.

She exhibited signs of fever and other symptoms of "gastrointestinal distress", Dr Lawrence said, which prevented her from coming to court.

Van-Rysewyk denies she failed to stop after hitting Brendan Braid as he cycled along the Old Princes Highway about 6.20am on January 5.

Mr Braid, a 58-year-old accountant from the Sutherland area, was flung from his bike and landed by the side of the road.

He suffered two fractured vertebrae, a broken femur, a cracked pelvis and fractured ankle.

A group of cyclists found Mr Braid lying by the road several minutes after the collision and phoned emergency services.

The magistrate adjourned the one-day hearing, to be re-listed at a later date. He told the court it was unlikely to be heard before November.