ITV News Meridian's Mike Pearse has been to the Royal Berkshire Hospital
The emergency department at the Royal Berkshire Hospital in Reading is the busiest it's ever been with more than 450 patients visiting a day.
Some patients are forced to wait all night - up to nine hours - to be seen by a doctor with ambulances backed up outside.
This demand has put pressure on services and a strain on staff with one consultant warning the "winter's going to be incredibly tough".
Simon Triscott, a consultant in emergency medicine, started working at the hospital just over seven years ago.
He said, at the time, they were seeing just over 300 patients on a "busy day".
That has since risen to more than 450 patients a day with people queuing for longer.
He said: "We don't want any patients to wait at all if we can possibly help it but we of course triage the sickest so we encourage anybody with a life-threatening emergency to of course come to this department and up and down the country with their needs and we will prioritise those patients.
"Sadly that means that those with less urgent needs, sadly have to wait longer."
The chief operating officer at the hospital, Dom Hardy, is urging people to ""think carefully" before going to the emergency department.
People are being encouraged to use other resources such as NHS 111 or their GP for help for non life threatening illnesses.
Mr Hardy said: "We need to work really closely with everyone in our health care system so I'd ask that anyone who thinks about using our emergency department yes to come here if it's a genuine emergency.
"If you've got chest pain or you're struggling to breath, absolutely we're the right place to be.
"But perhaps if you've got a minor illness, a sore throat, do try and see your GP, do go to your local pharmacy, do look online or ring NHS 111 because they are sources of advice and they can help you as well. Probably more quickly than we can."
Dom Hardy, chief operating officer, says people should try to use other resources
An urgent care centre has opened in Reading's Broad Street Mall where people can walk in and be seen by a doctor.
The hospital also has an Older Person's Emergency Department which is a six-bedded area where ambulances can be offloaded and patients triaged separately from the emergency department.
Mr Triscott added: "We are aware that this winter's going to be incredibly tough. We would encourage patients to seek help if they have life-threatening emergencies but utilise all those other resources too. It's going to be a challenge."
In a statement, the Department of Health said: "We understand the pressure hospitals are facing and we’re investing record amounts.
"More money is being made available for GP’s and many more pharmacists are being trained.
"Longer term new hospitals will be built improving things for patients."
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