One in five emergency patients at the county’s two main hospitals need not be there, according to new figures.
A survey of 500 patient visits to emergency departments at Kettering and Northampton hospitals found more than 100 could have gone to their doctor instead.
The survey also found almost all of the patients were registered with a doctor, but only a third contacted them before they attended hospital.
In response, NHS Northamptonshire and Milton Keynes is launching a television campaign aimed at encouraging people to use emergency departments appropriately.
The consequence of inappropriate use, the advert says, is that someone could die.
Emergency planning lead for the Northamptonshire Local Medical Committee Dr Jonathan Ireland said: “Yet again this winter all the frontline health services, from GPs to accident and emergency, have come under increasing pressure.
“The survey was done in response to this high level of demand in casualty departments to give an understanding of the choices the public make when they need help.
“Sometimes people would get a better service by accessing a different service.
“With the hard-hitting campaign the idea is to help people to understand that they have a choice of services and to make the best use of these resources.”
The survey also found more than a half of patients at the casualty departments had been seen less than six months before.
All patients asked could name an alternative service to the emergency department, but more than half had not contacted them. Other services include NHS Direct, the pharmacy, GP surgeries, walk-in centres and minor injury units.
The advert will also be on social media websites like Facebook.
Head of social marketing at NHS Northamptonshire and Milton Keynes Heidi King said: “The survey confirms we still have more work to do on educating people on the use of alternative services.”