Hay fever sufferers have been told they could be slapped with a £2,500 fine and points on their driving licence if they suffer from symptoms at the wheel.
The warning comes as a 'pollen bomb' continues to sweep the UK, with elevated levels expected until the weekend at least.
A pollen forecast from the Met Office warns that pollen counts in the next 24 hours will be 'Very High' across all of Wales, as well as western areas of England and Scotland.
'High' pollen is also predicted across almost every other area of the UK mainland, with only Grampian at a 'Medium' level.
Yolanda Clewlow, the UK Pollen Forecast Manager, said tree pollen was the "main factor in the forecast at the moment", with settled conditions helping spread particles from birch trees especially strongly this week.
Seasonal allergies can leave those affected with watering eyes and uncontrollable sneezing by coming into contact with just small amounts of pollen, with these effects often striking suddenly without warning.
Medications and over-the-counter remedies used to combat the symptoms are also known to cause changes in vision and drowsiness in some people.
All these can cause considerable difficulties in someone's ability to drive. Not only can the symptoms seriously endanger other road users, they may also land you in trouble if you are caught or end up being involved an accident.
The Highway Code states that you must not drive without due care and attention, an offence which can result in a £2,500 fine and three or more penalty points, according to Your Red Car. This could include sneezing at the wheel.
Giving some tips for managing your symptoms while on the road, the used car specialists say keeping the windows of your vehicle closed can be a necessary measure to prevent the wind blowing pollen in and causing a flare-up.
Keeping your car in a garage rather than parking outside on the drive or road will also stop pollen entering through vents while it is stationary, as these can be carried up through the vehicle.
A spokesperson from the firm added that changing air filters often may also help solve your problems if you find pollen is still finding its way inside.
Extra attention should also be paid to keeping the internal and external parts of your car clean when pollen levels are high.
Another factor that should be considered is the pollen you pick up yourself and bring inside your car, and putting clothes and blankets in a sealed bag before washing them later can help minimise issues.
Last year, a court heard how a van driver's uncontrollable sneezing fit saw him end up in a crash that sent two women to hospital.
Alexander Harkness, 29, drove his Peugeot van at speed into vehicles on Edinburgh’s City Bypass in the road accident on June 4, 2021.
He told police the rush hour collision came after a bout of sneezing was brought on by his hayfever.
Harkness eventually admitted driving without due care and consideration, and Sheriff Matthew Auchincloss imposed nine penalty points on his licence and fined him £1875.
