Bendigo Health senior doctor Simon Smith said emergency department staff often saw the "less pleasant side of Christmas" because of a higher proportion of alcohol-related presentations.

Dr Smith said people were encouraged to enjoy Christmas Day but not make decisions that put themselves or others in danger. 

He said alcohol-related presentations were not unusual, but that injuries at this time of year had a bigger impact on families.

Dr Smith said the emergency department was very busy during Christmas because other health services shut down for the holidays, putting pressure on resources.

Emergency department director Diana Badcock said mental health was another big issue at Christmas time. 

"Maybe it's time to go around and knock on a few doors and show a bit of Christmas cheer to make sure everyone's alright," she said.

Police had a similar message of caution, saying Christmas time was historically a period of serious injury collisions. 

Acting Senior Sergeant Della Nihill said a recent police operation revealed some disappointing driver behaviour.

Police found people not wearing seatbelts, using their mobile phones and a larger-than-usual number of people affected by drugs while driving. 

Between December 17 and 21 police detected nine drivers under the influence of illicit drugs - a figure of "huge concern". 

"That's just some of the offences we've got let alone all the unlicensed drivers, people driving unregistered motor vehicles and other traffic offences," Acting Senior Sergeant Nihill said.

"We want people to adhere to the road rules. Don't drive while affected by drugs or alcohol, be aware of your surroundings.

Acting Senior Sergeant Nihill said police would "saturate" central Victoria with breath testing over the Christmas and new year period.

"Road users can expect to be breath tested or drug tested anywhere on central Victorian roads at any time," she said.