Overview

• High temperatures can degrade active ingredients in tablets, inhalers, hormone patches, insulin and EpiPens and cause medicines to lose potency
• Diuretics, blood pressure medications and diabetes treatments can increase dehydration risk and impair the body’s ability to regulate heat
• Methotrexate users face extreme sun sensitivity that can lead to painful rashes, blistering and, in rare cases, serious infections
• Heat exposure can compromise the accuracy of medical devices such as blood glucose monitors if they are stored or used in hot conditions
• The MHRA urges patients to review storage instructions in patient leaflets and report any suspected heat-related drug failures through its Yellow Card scheme