Gardai stopped the driver of a tractor on Saturday night last and found him to be under the influence of cannabis and cocaine.
The driver was stopped at a routine checkpoint in Ballyshannon.
As well as being tested positive for cannabis and cocaine, he was also found to have a small amount of cannabis herb.
The driver is expected to appear at a future sitting of the local courts.
A Garda spokesperson said “Please do not drive under the influence of drugs or alcohol.
“You are playing roulette with your own life and the lives of others if you make the poor decision to do so.”