There has been a surge in demand at Christchurch Hospital's emergency department.
The ED has seen around 30 more people flocking to the hospital each day in the past few weeks - 380 people were seen in one day recently.
In an update, the district health board said people should call their GP if they need help late at night and are not sure if they should go to the hospital.
The DHB said people should only go to the hospital in an emergency.
Meanwhile, the acting chief executive's time has been extended.
It comes after a string of resignations from the leadership team in August, including the chief executive.
Canterbury has the highest deficit in the country at $170 million, and Crown monitor Lester Levy is working with the board to slash spending by $56.9 million this year.
The situation has seen also seen seven of the DHB's senior executive team members resign, and hundreds of hospital staff protest on the streets.
Acting chief executive Andrew Brant said his time at the board has been extended until the end of January but the new, fulltime CEO is expected to be announced before Christmas.