Some over-the-counter (OTC) medicines have the potential to make people feel sleepy. These include medicines that might be taken for allergy relief e.g. hayfever; cough; to prevent nausea e.g. travel sickness; and sleep remedies. It is important to always read the label as this will help you identify medicines liable to cause drowsiness.
Antihistamines are the most common cause of drowsiness. There are two main types:
• first generation (sedating) – can only be bought under the supervision of a pharmacist and are kept behind the counter.
• second generation (non-sedating) – have less potential to cause drowsiness.
Although this drowsiness can have a beneficial effect, such as helping someone sleep if they are suffering from a cough, it can also present a risk, particularly for people’s ability to drive safely.
Is everyone affected in the same way?
No. Some people are more sensitive than others to the particular ingredients known to cause drowsiness. There is increasing understanding that there is a genetic link and that some people metabolise the ingredients differently. However, it isn’t possible to predict how an individual will be affected at the point of taking the medicine: external factors such as taking more than one OTC medicine at the same time and drinking alcohol can also increase the risk of drowsiness. It is also important to note that illness itself can be a distraction for drivers if symptoms are not treated. People should ask their pharmacist for advice on choosing a suitable product.
Labelling and regulation
Medicines labelling is regulated and approved by the Medicines and Healthcare Products Regulatory Agency (MHRA).
Products that have the potential to cause drowsiness have to display a warning statement on the back of the pack. This reads:
“This medicine can make you feel sleepy. Do not drive while taking this medicine until you know how it makes you feel. See the leaflet inside for more information.”
The warning on packs and information in patient information leaflets (PILs) was reviewed and updated to reflect changes to the drug driving law (2015):
Drug Driving Law
It is illegal to drive if you’re unfit to do so because you have taken legal or illegal drugs. Legal drugs are prescription or over-the-counter medicines. If you’re taking them and not sure if you should drive, talk to your doctor, pharmacist or healthcare professional.
Further details can be found on the gov.uk website