The Medicines and Healthcare products Regulatory Agency (MHRA) issued a new alert on Friday, July 17, warning that heat and improper storage can compromise the safety and effectiveness of medications including inhalers, contraceptives, insulin, skin creams, and medical devices like blood glucose monitors and testing strips.
The alert comes as the UK experiences its third heatwave of the year, with forecasters from the Met Office and BBC Weather indicating that significant bursts of high heat will persist through July and into August. Many medications are designed to be stored below 25°C, and exposure to higher temperatures can destabilize them.
How Heat Affects Medications
According to the MHRA, medications left in warm bags, on sunny windowsills, or in parked cars can quickly degrade. Car interiors can exceed 40°C, even on mild days. Insulin, certain inhalers, skin creams, and some contraceptives are particularly vulnerable. Medical devices such as blood glucose monitors and insulin testing strips also require careful storage.
Dr Alison Cave, MHRA Chief Safety Officer, said: "During the summer, places such as parked cars, packed suitcases, caravans, and sunny rooms can get far hotter than people expect. For some medicines, these conditions can affect how well they work. Checking the storage instructions that come with your medicine, and storing it correctly, only takes a few minutes but can help ensure it remains safe and effective when you need it."
Storage Tips for Hot Weather
The MHRA advises keeping medicines in a cool, dry place out of direct sunlight. Avoid storing them in bathrooms or near heat sources. Always check the patient information leaflet or packaging for specific storage instructions. Some medicines require refrigeration; others need protection from light or heat.
Signs of heat damage include changes in colour, unusual odour, or melting. If a medication appears damaged, consult a pharmacist. Never leave medicines in cars, suitcases, or caravans during travel.
Reporting Concerns
Anyone who suspects their medicine is not working as expected should speak to a pharmacist or doctor and report suspected issues to the MHRA Yellow Card scheme. The MHRA offers further advice on 'summer-proof your health' on its website.
