Visiting has been suspended on a ward at the Royal Lancaster Infirmary after an outbreak of norovirus.
The virus has affected patients and staff, said the trust which runs the hospital.
The University Hospitals of Morecambe Bay NHS Foundation Trust said the suspension of visiting on Ward 35 will remain in place until a review next week.
"We wish to reassure everyone that all steps are being taken to contain the virus and stop it spreading," said a trust spokesperson.
"Relatives and carers of patients on Ward 35 are being contacted by the team to let them know about the suspension of visiting.
"A further update will be shared on our communications channels when possible.
"Any calls are to go through the RLI Switchboard on 01524 65944.
"Thank you to everyone for your patience and support at this time."
Norovirus, also called the 'winter vomiting bug', is a stomach bug that causes vomiting and diarrhoea. It can be very unpleasant, but usually goes away in about two days.
The main symptoms of norovirus are:
- feeling sick (nausea)
- diarrhoea
- being sick (vomiting)
You may also have:
- a high temperature
- a headache
- aching arms and legs