Dr Ranj Singh, a BBC medical expert, issued a warning on BBC Morning Live as the UK braces for temperatures soaring up to 40°C. The Met Office and UK Health Security Agency have declared a red alert health warning. Dr Singh highlighted that extreme heat alters how the body responds to certain medications, increasing the risk of serious side effects.
Medications Affected by Heat
Dr Singh listed several types of medication that require extra caution during the heatwave. These include diuretics (water tablets), blood pressure medications, antipsychotics, ADHD drugs, certain antibiotics like doxycycline, insulin, hormone patches, and Epipens. He emphasized that patients on these medications should be vigilant about hydration and storage.
“If you’re on diuretics or blood pressure tablets, you are more likely to be at risk of dehydration,” Dr Singh said. “Be very careful with your water intake.” He also noted that antipsychotic and ADHD medications impair the body’s ability to regulate temperature, so users need to pay extra attention to staying cool.
Photosensitivity and Insulin Absorption
Dr Singh warned that antibiotics such as doxycycline increase photosensitivity, making skin more vulnerable to sun damage. For diabetics using insulin, he explained: “Because more blood supply goes to your skin, you may absorb insulin faster, raising your risk of hypos.” He advised monitoring blood sugar levels closely.
Storage of medications is also critical. “Insulin and Epipens are temperature-sensitive,” Dr Singh said. “You might need to pop them in the fridge. Hormone patches and some antibiotics also require cool, dry storage.”
How Heat Affects the Body
Dr Singh explained that the body functions optimally at around 37°C. In heat, blood flows to the skin to radiate heat and promote sweating. However, this reduces blood flow to organs: “You get less blood to your kidneys, so you wee less; less to your brain, so you feel foggy; and less to your stomach, reducing appetite.” Combined with sweating, this can lead to dehydration.
He also mentioned prickly heat, a non-dangerous but irritating condition caused by trapped sweat, which can be managed by washing and cooling the skin. Prolonged heat exposure can lead to heat exhaustion and heat stroke, which require medical attention.
Advice for the Public
Dr Singh urged anyone feeling unwell to look for signs of heat exhaustion or heat stroke and to seek medical advice early. “Make sure you’re drinking enough water and controlling your temperature,” he added.
