Gardaí arrested a motorist in Buncrana after the car they were travelling in was clocked doing 168km/hr inside a 80km/hr zone.
The driver also failed a roadside breath test.
The driver tested positive for excess alcohol a second in a nearby Gardai station.
"Arrested and taken to Garda Station where further breath analysis carried out. Over the limit. Never drink & Drive!," said Gardai on Twitter.