Five motorists were arrested in the Melton area for being under the influence of alcohol or drugs.
Arrests were made in Melton, Somerby and Kirby Bellars, with four being for drink-driving and the other for drug-driving.
Police say 99 drivers were arrested for these offences across Leicestershire, almost double the number for the same month in 2016.
Jonathan Clarkson, spokesperson for the Leicester, Leicestershire and Rutland Road Safety Partnership, said: “The number of arrests is significantly up on December 2016, when we saw 50 people arrested, including 46 drink and four drug.
“What is particularly alarming is the number of younger drivers, 33 in total, who chose to put themselves at risk - that’s a third of the overall arrests.
“Equally concerning is the increase in the number of drug drivers being detained, over 20 in this case.”
Regarding the arrests for these offences across the county, 35 were made following a road traffic collision and 33 of the arrested drivers were aged 25 or under. The arrested drivers included 21 in the Charnwood district.
The highest road side breath test recorded during December was 141, moe than four times the legal limit.
Mr Clarkson added:“Although our seasonal campaign has come to an end officers will continue to patrol across the force area to make our roads safer, including our towns, villages and rural areas.
“Our message to drivers is ‘if you choose to drink drug drive you will get caught’.”