Chennai's heat is no longer just uncomfortable — doctors say it is starting to wear down the body, organ by organ, and that this is the season to get serious about self-care. As temperatures climb and hot, dry winds blow through the city, clinicians are seeing more patients with dehydration, exhaustion, sunburn, eye irritation, and breathing trouble.
High Humidity Adds Strain
High humidity makes it harder for sweat to evaporate, slowing the body's natural cooling system and putting extra strain on the heart, kidneys, and brain. Those spending long hours outdoors — traffic police, marketing executives, street vendors, as well as children and older adults — are among the most vulnerable. Doctors say simple measures — drinking water regularly, avoiding midday sun, and using basic protection such as helmets, visors, sunglasses, sunscreen lotions, and umbrellas — can sharply cut the risk of serious heat-related illness.
Eyes: Not Just Irritation
Ophthalmologists say summer routinely brings a spike in complaints of dryness, redness, itching, and a gritty or burning sensation, particularly among people exposed to sun and dust on the roads. "Such cases have increased by nearly 20%. Constant exposure to sunlight can irritate the eyes and, over time, cause lasting damage," said Dr M B Dinesh, senior cataract and refractive surgeon at Maxivision Super Speciality Eye Hospitals. While many dismiss these as minor irritations, specialists warn that repeated, unprotected exposure to ultraviolet rays can, over time, damage the surface of the eye and the lens. "Long-term UV exposure has been linked to conditions such as cataracts, photokeratitis, and pterygium, all of which can affect vision if left untreated," he said.
Skin: Barrier Under Stress
Sunburn, tanning, prickly heat, and sun-induced rashes intensify with summer. Face, neck, arms, and hands, which are exposed directly to sunlight, are at the highest risk, especially in people with outdoor jobs or sensitive skin. "We advise patients to bathe twice a day and use cold-water sponging for immediate relief from prickly heat. People who sweat less are also prone to dry, itchy skin, especially children and senior citizens. Staying hydrated is essential," said Dr J Benedict Reji, assistant professor of dermatology at Government Stanley Medical College Hospital. Dermatologists say loose cotton clothing, hats, or umbrellas are a must when people are stepping out in the sun. They also recommend liberal use of broad-spectrum sunscreen — at least SPF 30, ideally SPF 50 with a PA+++ rating, applied twice a day. Children and older adults, who tend to sweat less and may not notice early signs of overheating, are especially prone to itchy, inflamed skin and need closer monitoring.
Brain and Nerves: Heat and Confusion
Neurologists say extreme heat can disrupt the brain's ability to regulate temperature and maintain normal function. Heat exhaustion often shows up first as fatigue, irritability, agitation, or confusion, while heat stroke — a medical emergency — can cause disorientation, seizures, or loss of consciousness as body temperature soars. "Heat exhaustion is common in people who present with agitation, confusion, and fatigue. Heat stroke, meanwhile, is far more severe. During summer, we see an increase in migraine and seizure cases. Even those with no prior history of seizures may experience one due to excessive sweating and electrolyte imbalance," said Dr S Srividhya, associate consultant, Department of Neurology, Rela Hospital. For vulnerable people, it is important to replenish electrolytes by drinking water along with oral rehydration solutions, homemade salted lemon or buttermilk, or low-sugar electrolyte drinks, especially after heavy sweating or illness. She added that children, older adults, and those with underlying kidney or cardiac conditions are particularly vulnerable, and that anyone with sudden confusion, fainting, or fits should be taken straight to an emergency room.
Kidneys and Heart: Silent Strain
Nephrologists warn that repeated days of heavy sweating without adequate fluid intake can reduce blood volume, cutting blood flow to the kidneys and increasing the risk of acute kidney injury. "Summer also sees a sharp rise in kidney stone cases. Reduced water intake increases the concentration of minerals such as calcium and uric acid, which can crystallize and form stones," said Dr Jayanivash J, consultant nephrologist at SIMS Hospital. Symptoms such as dizziness, blackouts, very dark urine, or a sharp drop in urine output should prompt urgent medical review, he added.
Cardiologists, meanwhile, caution that heat forces the heart to work harder as blood vessels widen to release heat through the skin. Dehydration thickens the blood and can raise the risk of clots, potentially triggering conditions such as pulmonary embolism, stroke, or heart attack in vulnerable people. "People who stand for prolonged periods or travel long distances are particularly vulnerable to blood clots in the legs, which can affect blood flow to the heart," said Dr J Ashok Kumar, cardiologist at Revathi Medical Centre. Those who stand for long hours, travel on packed buses or trains, or already have heart disease are advised to take short walking and water breaks, avoid prolonged standing in direct sun, and follow their doctor's guidance on safe fluid limits.
