With temperatures soaring in the Capital and the India Meteorological Department (IMD) issuing an orange alert, hospitals across Delhi have begun reporting sporadic cases of heat-related illnesses.Major hospitals said they have not yet reported any cases of heat stroke, a severe and potentially life-threatening condition. However, some facilities said patients have been reporting symptoms of heat exhaustion.Heat exhaustion occurs when the body overheats and loses excessive water and salts, usually due to prolonged exposure to high temperatures. If left untreated, it can progress to heat stroke.At the Centre-run Ram Manohar Lohia (RML) Hospital, doctors confirmed that a patient with heat exhaustion symptoms visited on Tuesday. Meanwhile, doctors at Indraprastha Apollo Hospital — Delhi’s largest private hospital—said they have seen a rise in cases linked to heat exposure, with patients complaining of dehydration, headaches, cramps, and rashes.As the Capital entered its second consecutive day under the grip of a heatwave, Delhi recorded a maximum temperature of 44.5 degrees Celsius, 4.1 notches above normal on Wednesday. Against this backdrop, hospitals in Delhi have also stepped up preparedness to tackle heatwave by ensuring the availability of air-conditioners, coolers, and drinking water facilities for patients and attendants.According to Dr Prabhat Kumar Jha, Director of Internal Medicine at Medanta Gurugram, older adults are among the most vulnerable to heat-related illnesses, as their body’s ability to regulate temperature declines with age. People with chronic illnesses like heart disease, diabetes, kidney disease, or respiratory disorders are particularly susceptible to complications from dehydration and heat stress. Children and infants are equally at risk, since they tend to dehydrate more quickly and may not recognise or communicate symptoms effectively, he said.“Certain medications can also reduce the body’s ability to cope with high temperatures. Outdoor workers, including construction workers, delivery personnel, traffic police, and agricultural labourers, are exposed to prolonged direct heat and therefore face elevated risks,” Dr Jha noted. According to Dr Jha, pregnant women and individuals without access to adequate cooling or hydration may also be more vulnerable.Story continues below this ad“These groups should take extra precautions during heatwaves and seek medical attention promptly if symptoms of heat-related illness develop,” he stressed.Drawing a distinction between heat exhaustion and heat stroke, Dr Jha clarified that while both are caused by excessive heat exposure, heat stroke is the more life-threatening of the two. “A person with heat exhaustion may experience heavy sweating, weakness, dizziness, headache, nausea, muscle cramps, and extreme thirst. Their skin may feel cool, pale, or clammy, and they may feel faint or unusually tired,” he explained.“Heat stroke, on the other hand, is a medical emergency. Warning signs include a very high body temperature, confusion, disorientation, slurred speech, unusual behaviour, seizures, or loss of consciousness. The skin may feel hot and dry, although sweating can still occur in some cases,” he added.The key difference, he emphasised, is that in heat stroke the body’s temperature regulation system begins to fail, affecting the brain and vital organs. Anyone showing signs of confusion, altered mental status, or collapse during extreme heat should receive immediate medical attention, Dr Jha cautioned.Story continues below this adAs per Dr Jha, while not every heat-related illness requires hospitalisation, certain symptoms should never be ignored. “People experiencing mild heat exhaustion often improve with rest, hydration, and cooling measures. However, medical evaluation becomes necessary if symptoms do not improve within a short period, if vomiting prevents adequate fluid intake, or if the person has underlying conditions such as heart disease, kidney disease, diabetes, or is of advanced age,” Dr Jha said.“Hospital admission is usually required when heat stroke is suspected — signs include confusion, altered mental status, unconsciousness, seizures, difficulty breathing, very high body temperature, or organ dysfunction. These patients may need intravenous fluids, active cooling, and close monitoring,” he added, warning that delaying treatment significantly increases the risk of organ-related complications.On preventive measures, Dr Jha advised avoiding outdoor activity between 12 noon and 4 pm, when temperatures peak. In rural areas, farmers should complete fieldwork in the early morning or resume after 3 – 4 pm, Dr Jha said. He emphasised that drinking water regularly, even when not feeling thirsty, is key.“Outdoor workers should take frequent breaks in shaded areas and carry water or ORS. Wearing loose-fitting, light-coloured cotton clothing, along with a cap, scarf, umbrella, or sunglasses, can further help the body stay cool. Alcohol and highly caffeinated beverages, which accelerate dehydration, should be avoided during peak hours,” he said.Story continues below this ad“Awareness and early action remain the best ways to prevent serious heat-related complications during the summer months,” Dr Jha concluded. While acknowledging that Medanta Gurugram has not witnessed any confirmed cases of heat stroke or heat exhaustion so far, Dr Jha also noted that the risk of heat-related illnesses is certainly increasing amid rising temperatures.Meanwhile, IMD has also issued an orange alert for Thursday, with the minimum temperature likely to settle around 28 degrees Celsius and the maximum expected to touch 46 degrees Celsius. Delhi’s air quality was recorded at 168, in the ‘moderate’ category on Wednesday, a slight improvement from the AQI of 208 logged in the ‘poor’ category on Tuesday.