Drivers are being reminded of the potential dangers of driving the morning after a night out if alcohol was consumed.

The Road Safety Authority (RSA) is highlighting the issue to coincide with the St Patrick's Festival, which runs from March 17-20. It is reminding people that they could still be over the legal alcohol limit if they drive the morning after a night out.

The authority highlighted the fact that in the five-year period 2011-2015, 15 people died and 34 were seriously injured on Irish roads between March 16-18.

According to RSA chief executive, Moyagh Murdock, this is traditionally a time of year when people enjoy a break from work, college and school, however they must still act responsibly when it comes to road safety.

"We're not suggesting that people don't enjoy themselves, but we would urge people to act safely and responsibly, particularly when it comes to alcohol and road use. If you decide to go out for the night, leave the car at home and take the sensible option by using a designated driver or getting a taxi or public transport to and from your destination," she said.

She emphasised that depending on how much alcohol you consumed the night before, you may still be over the limit the next morning without even realising it.

"It roughly takes you about one hour for your body to get rid of one unit of alcohol - that's a half pint or standard glass of wine. If you got to bed in the early hours and didn't get a good night's sleep, this will magnify the impairing effects of any alcohol in your system," Ms Murdock explained.

Also commenting on this issue, Chief Superintendent Aidan Reid of the Garda National Traffic Bureau, reminded road users that drink-driving can destroy lives.

"At best, you could lose your licence but far worse, and far more difficult to live with, is the possibility of seriously injuring or killing someone on the roads.

"Our members will be patrolling the road network throughout the country over the St Patrick's Festival period in marked and unmarked vehicles and would like to remind drivers that in addition to mandatory breath testing, they can be breath tested if they commit any road traffic offence. So please make sensible choices when using the roads and never, ever drink and drive," he said.

He also reminded drivers of the potential danger of driving the morning after a night out and pointed out that 12% of all drink driving arrests occur between the hours of 8am and 2pm. Among these, almost one-third happen on a Sunday, peaking between 11am and 2pm.

Meanwhile, Ms Murdock also reminded pedestrians of the dangers of consuming alcohol.

"It's hard to believe but two-thirds of pedestrians killed on our roads have consumed alcohol.

"Alcohol makes you unsteady on your feet and less capable of crossing the road safely or staying upright. It also impairs your judgement, making you more likely to step out in front of oncoming traffic because your ability to judge safety and distance is significantly impaired," she noted.

She urged people who are going out to plan their journey home by organising a lift or using a taxi or public transport.

"I would also encourage people to look out for each other - if your friend or relative is under the influence of alcohol, make sure they get home safely," she added.