New roadside drug testing will come into effect from tomorrow.
Under the rules, drivers could lose their licence if they’ve taken cannabis, cocaine, opiates or benzos.
It’s estimated that drug driving is a factor in one in ten fatal crashes.
The new campaign is mainly aimed at drivers who smoke cannabis and those who take benzos like xanax or valium without a proper prescription.
For the cannabis – along with cocaine and heroin – just having a certain level of the drug in your system is enough for it to be illegal.
However with the benzos – it will only be an offence if the gardai can prove your driving was impaired.
Assistant Commissioner Michael Finn is confident that the new testing will work despite the recent garda breath test scandal.
He said: "I am happy that systems have been put in place, and that we're doing the right things."
It comes as the Irish Pharmacy Union has urged motorists to talk to their pharmacist to ensure they do not break the law.
Pharmacist Ann Marie Horan said: "It is extremely important when taking any medicines that people ensure that they are taking the prescribed dose."
The new roadside drug testing takes about ten minutes to do and it goes live from midnight.