Gardaí have arrested four drivers on suspicion of drink and drug-driving since Friday evening.
One driver was detained after flashing an unmarked patrol car on the N4 dual carriageway -- and then overtaking at 130 km/h.
The driver was arrested on suspicion of drink driving.
Gardaí are warning people to slow down, put away mobile phones, and never drive under the influence of an intoxicant.
The Road Safety Authority says research shows young men are the most vulnerable group on the roads when it comes to drink and drug-driving.