Just 58 drivers have tested positive for drugs in the eight months since new garda roadside tests were introduced.
The Irish Times reports that only 13 motorists tested positive in the first four months after they were introduced.
From April to November last year 1,856 Gardaí had received training to carry out the tests - out of over 13,000 members.
Independents 4 Change TD Tommy Broughan obtained the figures through a parliamentary question.
When the new tests were introduced, Gardaí had estimated that they would carry out 50,000 roadside drug tests a year.
Drivers were traditionally tested for potential drug intoxication through Roadside Impairment Testing, which included the likes of walking tests and 'finger-to-nose' tests.
The new drug testing devices now allows officers to test a sample of a driver's saliva for the presence of drugs such as cocaine, heroin, Valium and cannabis.