Anyone with a planned surgery or an outpatient appointment should still turn up as planned.
The changes are in place until further notice while there are a number of viruses circulating and the hospitals are at capacity, she said.
"Thank you for your cooperation and understanding as we all work to protect our vulnerable patients and staff."
Summary of key changes for Christchurch and Burwood Hospitals:
• Visiting is restricted to one person at a time per patient, for essential purposes only.
• People should stay home if they're unwell.
• Children are not permitted to visit, unless an exception has been granted by the relevant Charge Nurse of the ward being visited, until further notice.
• It is recommended that anyone visiting wears a face mask or other face covering.