Nearly two-fifths of UK drivers say they have been so tired they have feared falling asleep at the wheel, while one in eight admit to having done so, according to research carried out for the AA’s Charitable Trust.

Road safety charities emphasise the importance of looking for a safe place to stop if you feel tired, having a caffeinated drink, and ideally a 15-minute nap to allow time for the caffeine to kick in. However, “this should be seen as a temporary fix and does not replace the need for adequate sleep”, said Prof Ashleigh Filtness, a driver fatigue expert for Road Safety GB.

Other tips include avoiding driving when you would normally be sleeping, and being extra careful between 2pm and 4pm (especially after you have eaten), when alertness naturally dips, causing drowsiness and reduced concentration.

New parents, people juggling busy schedules, and those with sleep disorders such as narcolepsy, insomnia or sleep apnoea are at particularly high risk of being in a fatigue-related crash, as are shift workers – especially those working irregular shifts and switching from day to night shifts without sufficient time off for their body clocks to adjust.

If you are planning a long drive, be sure to schedule sufficient time for regular breaks, and plan an overnight stop if your journey is longer than 12 hours. If you are tired, try to take the train or bus instead.

Be particularly wary of long journeys on monotonous roads such as motorways. Research has suggested that driving deteriorates after two hours without a break. The road safety charity Brake recommends taking a rest every two hours.