The NHS in Northamptonshire is asking people with symptoms of colds, flu and winter sickness not to visit hospitals over the festive period.
These conditions are best treated by self-care, a spokesman said.
This means staying indoors, resting and using medication available over the counter.
He said people put emergency services under extreme pressure by visiting emergency departments, calling out of hours medical services and GPs.
Rather than putting extra strain on services vital for real emergencies at this busy time of year people with cold and flu symptoms should use available medication and if worried visit a pharmacist for expert advice.
An NHS Northamptonshire spokesman said: "This is the peak time of the year for colds and flu.
"If you're generally fit and healthy, you can usually manage the symptoms of a cold or flu yourself without seeing a doctor.
"Turning up at A&E with colds or flu, or diarrhoea and vomiting, is not the right choice.
"There is always pressure on our dedicated staff at this time of year, and if staff become sick with these viruses themselves, then it puts extra strain on the service."