As humid heat bears down across the country, the questions around staying safe go well beyond drinking enough water. Dr Mohemed Sanowfer, consultant, internal medicine at KIMSHEALTH, Thiruvananthapuram, tells Unnikrishnan S about staying safe in the heat. Edited excerpts:
Is plain water enough when it’s humid, or do we need sports drinks? And what’s the golden rule for how much to drink?
For most people, plain water is the best hydration. Electrolytes become necessary only during prolonged exertion beyond 60-90 minutes, heavy sweating, or early heat exhaustion. Most commercial sports drinks are too sugary and can actually slow fluid absorption. A simple homemade ORS – one litre of water with a pinch of salt and a teaspoon of sugar – works just as well. The golden rule is not to wait for thirst, as it is signal you are already late. Aim for pale-yellow urine and drink between 2.5-3.5 litres daily in peak summer, more if you are spending time outdoors.
Can drinking ice-cold water during a heatwave shock the system? Is cool water better than ice-cold for bringing down body temperature?
Ice-cold water is not dangerous, but extremes are unnecessary. Very cold water can briefly trigger a vagal response in some people and may slightly reduce the body’s ability to lose heat through the skin. Cool water, rather than ice-cold, is the practical ideal. That said, the real priority is straightforward, drink enough, at whatever temperature is available.
Can common medicines for BP or allergies quietly make someone more vulnerable to heat?
This is something that is often missed. Several widely used drugs reduce the body’s heat tolerance. Diuretics increase dehydration risk, beta-blockers blunt the heart’s compensatory response, older antihistamines and anticholinergics reduce sweating, antipsychotics impair the brain’s temperature regulation, and ACE inhibitors or ARBs alter how the kidneys handle stress. There is no need to stop these medications, but patients on them need stricter hydration, should avoid peak heat hours, and require closer clinical review through summer.
Where should ice packs be placed to cool someone down fastest? Does the forehead actually help?
The forehead feels soothing but is not the most effective target. The priority should be pulse points — areas where the blood flow is closest to the surface. Placing cold packs or wet towels on the neck, armpits, groin, and inner wrists cools the circulating blood directly and brings down core temperature far more efficiently. A wet towel combined with a fan remains one of the simplest and most effective methods. If using ice packs, wrap them to avoid skin injury.
When does a headache or dizziness stop being minor and become a medical emergency?
Most mild symptoms settle with rest and fluids, but certain signs cannot wait. Confusion, disorientation, or unusual behaviour means the brain is overheating, that alone warrants urgent care. If sweating has stopped and the skin is hot, red and dry, the body’s cooling system has failed and this is heatstroke. A body temperature at or above 40°C, seizures, collapse, persistent vomiting, or an inability to stand or stay awake are all emergencies where minutes matter. In children, sudden quietness or limpness, and in the elderly, any subtle shift in behaviour, should never be dismissed.