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Rules of the Road

RSA handbook · 292 pages · 271 embedded images

Factors that affect safe driving

Page 175

Drugs

It is against the law to drive a car, motor bike, truck, bus, pedal bike or an animal-drawn vehicle while ‘under the influence of an intoxicant to such an extent as to be incapable of having control of the vehicle’.

Intoxicants include alcohol and drugs, whether taken separately or together. The word ‘drugs’ here includes legal prescribed and over the counter (OTC) medicines.

If a Garda suspects you of driving under the influence of drugs, they may require a saliva sample and for you to perform ‘impairment tests’. Before conducting such tests, a Garda will ascertain whether you have any disability or medical condition which you think might prevent you from participating in the relevant test. These impairment tests may involve the performance of the following five tests: a ‘pupil dilation’ test; a test of your ability to balance; a ‘walk and turn’ test; a ‘one leg stand’ test; and a ‘finger to nose’ test.

It is an offence to refuse to perform impairment tests if required by a Garda.

A Garda may conclude from observing your ability to perform these tests that your ability to drive is impaired and consequently arrest you. The results of these tests may be used as evidence, along with any blood or urine samples taken and tested for the presence of any drugs, in order to convict you of driving while under the influence of an intoxicant.

The Gardaí can use preliminary drug testing devices, called the Drager Drug test 5000, at the roadside or in a Garda station to test a person’s oral fluid for Cannabis, Cocaine, Opiates and Benzodiazepines. If positive, a blood specimen can be taken, which will be sent to the Medical Bureau of Road Safety (MBRS) for evidential testing.

If the Garda forms the opinion that you are impaired and you have not had a preliminary drug test, or the results of that test were negative, they can request either a blood or urine specimen, which will be sent to the Medical Bureau of Road Safety for testing.

The penalty for drug driving is the same as for drink driving – a maximum of €5,000 fine and up to 6 months imprisonment on summary conviction.

Extracted from the RSA Rules of the Road, Revision 9, May 2026. Source PDF · reuse permission unconfirmed.