Overview

• The UK Health Security Agency has reiterated that patients on diuretics, beta blockers, antipsychotics and SSRIs face elevated risks of heat-related illness during the fourth heatwave of summer 2025.
• The Medicines and Healthcare products Regulatory Agency warns that insulin and metformin can worsen dehydration and obscure early symptoms of overheating.
• The Met Office forecasts sustained highs above 30°C across England and Wales with strong August sunshine and isolated thunderstorms developing this week.
• Official guidance urges people to store medications within recommended temperature ranges, sip water slowly throughout the day and avoid strenuous activity during peak heat hours.
• Anyone who feels unwell in the heat is advised to move to a cooler place immediately and seek medical advice to prevent serious complications.