Lancashire Police patrols were out and about over the festive period and stopped hundreds of motorists as part of its Christmas road safety campaign.
Officers breath-tested drivers at checkpoints and carried out random stops on vehicles, as well as acting on intelligence from members of the public.
A total of 240 people were arrested in December, with 137 of those held on suspicion of drink-driving.
Another 71 arrests were in relation to drug-driving and the other 32 were in relation to motorists failing to give a sample or having their judgment significantly impaired by drink or drugs.
One of the arrests was in relation to a fatal Boxing Day crash in Skelmersdale where a pedestrian aged in his 30s was killed.
A 29-year-old man from Skelmersdale was arrested at the scene on suspicion of drug driving and causing death by careless driving while under the influence of drink or drugs.
Ch Insp Pat Worden, of Lancashire Police, said: "First and foremost we must thank those members of the public – by far the majority – who followed the law and made arrangements that didn’t involve them drink or drug-driving.
"Unfortunately we know that at Christmas more people are willing to take the risk than at other times of year and this last month saw officers stop 240 people who believed the law did not apply to them.
"Drinking or taking drugs before driving is completely unacceptable at any time and our efforts to catch those responsible are constantly ongoing.
"Christmas may be over but we will continue to carry out regular enforcement activity and take action against anyone who breaks the law and puts others’ lives at risk in this way."