I found this on line, under Lutheran Senior Services:
"One of the primary mechanisms the body uses to cool itself is sweating. However, as we grow older, sweat glands don’t produce as much as they once did. This impairs the body’s primary means of dissipating excess heat, leaving our loved ones more prone to overheating.
On top of that, the blood vessels in the skin—which dilate to allow more blood flow and facilitate cooling—become less reactive. This reduced vascular response makes it more challenging for the body to redistribute heat effectively.
Common medications, such as diuretics, beta-blockers, and antidepressants, further compromise the body’s temperature control mechanisms. They interfere with the regulation of blood pressure, heart rate, and fluid balance, increasing the risk of heat-related illnesses like heat exhaustion and heatstroke."
So please drink more, stay in the shade and use a fan. If you are feeling tired or dizzy, then rest when need.