UK health agencies warn heatwave can degrade medications

A record-breaking heatwave in the United Kingdom, with temperatures above 34 °C for a seventh consecutive day, prompted amber heat‑health alerts from the UK Health Security Agency (UKHSA). Health officials warned that prolonged exposure to hot conditions can compromise the effectiveness of a wide range of medicines and devices.

The UKHSA, in coordination with the Medicines and Healthcare products Regulatory Agency (MHRA), issued guidance that insulin, liquid antibiotics, asthma inhalers, hormone patches, EpiPens and other temperature‑sensitive drugs may lose potency when stored above 25 °C, such as in cars, windowsills or hot bags. Diuretics, blood‑pressure medicines, SSRIs, hormonal contraception and stimulant medications were also highlighted as vulnerable, with potential side‑effects including dehydration, altered blood‑pressure regulation and reduced contraceptive efficacy. The agencies advised the public to keep medicines in cool, shaded places, check for any colour, smell or texture changes, and to consult pharmacists or doctors if unsure.

Pharmacist Jason Murphy of Chemist4U echoed the warnings, providing a detailed list of common drugs that can be affected and emphasizing the risk of unintended pregnancy from heat‑damaged contraceptives. Meanwhile, TV doctor Amir Khan clarified that for most people ordinary hydration with water is sufficient, and electrolytes are only needed during prolonged intense exercise.

Overall, the advisories aim to prevent medication failure and related health complications during the ongoing summer heat.