People have been urged not to call 999 over the Bank Holiday weekend unless there is an emergency.
Yorkshire Ambulance Service said it received an increased number of alcohol-related calls on bank holidays.
And it said people whose calls are not an emergency should call the NHS 111 number instead, to avoid putting unnecessary pressure on the service.
David Williams, deputy director of operations at the trust, said: “The high volume of calls we receive during the bank holiday periods puts the service under increased strain and makes it more difficult for us to ensure we can get to all of the people calling 999 for ambulance assistance quickly.
“Typically, more people will be out and about socialising with family and friends which can lead to an increase in illness and injury and, as many people will be celebrating the extra day off with alcoholic drinks, we usually see a rise in alcohol-fuelled incidents too. We want people to enjoy themselves but ask that they do it sensibly and look after each other.
“We have plans in place to help manage the impact of the additional demand this weekend will bring. However, people with minor illnesses and injuries should consider the variety of other NHS healthcare services available to them for advice and treatment for non-emergencies and less serious conditions.”
NHS 111 is an urgent care helpline which operates 24 hours a day.
People can also get help at an NHS walk-in centre or minor injuries unit which are usually open early morning until late at night.
And local pharmacists can provide advice on illnesses and medicines.