When temperatures stay high for several days, the heat can damage medicines you keep at home and affect how well they may work.
During a heatwave, people often focus on drinking enough water and avoiding the sun. Only a few think about what the heat could do to their medicines.
Some medicines lose their effectiveness when exposed to high temperatures, even if they look normal.
How does hot weather affect medicines?
Many medicines need to stay below 25degrees Celsius, although storage instructions differ from one product to another.
High temperatures can affect the ingredients in certain medicines and reduce how well they work.
Heat can also change their appearance, creams may separate. Capsules may soften and some liquid medicines may change in consistency.
The UK’s Medicines and Healthcare products Regulatory Agency warns that heat can affect common treatments, including tablets, inhalers and insulin.
Where should you keep medicines during a heatwave?
Choose a cool, dry place away from direct sunlight.
Avoid leaving medicines on windowsills, in hot kitchens or in bathrooms where heat and moisture can build up.
Never leave medicines inside a parked car, even for a short period.
If you need to travel, use a suitable insulated medicine bag where necessary.
Avoid placing medicines directly against ice packs because freezing can also damage some treatments.
Only refrigerate medicines when their storage instructions require or allow it.
How can you tell if heat has damaged your medicine?
Look out for changes in colour, texture or appearance.
Tablets may become soft or crumbly, while creams may separate and liquids may turn cloudy.