The judge-alone trial of Tavake Lee Pikula, 34, was about to begin in the ACT Supreme Court on Monday morning when the incident occurred.

Pikula suddenly charged towards the public gallery and made brief physical contact with a woman, during which he seemed to receive and swallow something before being wrestled to the ground by three ACT Corrective Services officers.

The woman, who was quickly removed from the courtroom, swore at the officers and called them "putrid dogs" as they detained a growling Pikula.

A second woman urged Pikula to "settle down, son" as he was handcuffed and hauled away.

Justice Chrissa Loukas-Karlsson had yet to enter the courtroom to start the trial, which was delayed until at least Tuesday so that doctors could monitor Pikula's condition ahead of a decision on when the case would go ahead.

When the trial does begin, it is expected that Pikula will appear via audio-visual link instead of being brought back to court in person.

The trial will deal with allegations that Pikula robbed the Narrabundah Takeaway while armed with a knife on December 2 last year.

The McKellar man allegedly stole the shop owner's handbag, which contained $900 and items including a phone and bank cards.

He is also accused of taking $50 from a cash register in what prosecutors have previously described as a "brazen" daylight robbery witnessed by the shop owner's five-year-old son.

Pikula denies the allegations and has pleaded not guilty to one count of aggravated robbery.