Live chat: Top Doctors Warn 'Normal' Headaches and Fatigue Could Signal a Life-threatening Heatstroke

As brutal heatwaves continue sweeping across India, doctors are warning that many people may be ignoring early signs of heat-related illness without realising the danger. Symptoms such as headaches, dizziness, unusual fatigue, nausea, excessive sweating, muscle cramps, and weakness are often dismissed as “normal summer tiredness,” but according to doctors, they can actually signal the beginning of heat exhaustion - a potentially serious condition caused by dehydration and the body overheating. According to physicians, rising temperatures increase fluid and salt loss through sweat, making it harder for the body to regulate temperature and maintain healthy blood circulation. If left untreated, heat exhaustion can rapidly progress into heatstroke,

a medical emergency that may cause confusion, fainting, seizures, organ damage, and even death. Top doctors from across India address some of your most worrying heat-wave related queries, which can help you to figure out how to survive the brutal temperature surge without falling sick.

• Dr. R. Navin, Consultant Physician and Diabetologist, Apollo Medical Centre in Valasaravakkam, Chennai
• Dr Manjusha Agarwal, Consultant- Internal Medicine, Gleneagles Hospital, Mumbai
• Dr. Souradeep Chowdhury, Associate Consultant, Internal Medicine, Medanta, Noida
• Dr. Seema Dhir, Unit Head & Sr. Consultant, Internal Medicine, Artemis Hospitals, New Delhi
• Dr. Sharadchandra Yadav, Consultant, ICU Care, Ruby Hall Clinic, Pune
• Dr. Sulaiman Ladhani, consultant chest physician, Saifee Hospital, Mumbai

Why do I get headaches and dizziness more often during very hot weather?

In the summer months, people experience increased occurrences of headaches, dizziness, weakness, and fatigue due to large amounts of water and salt being lost from sweat through sweating. Dehydration prevents the body from cooling itself effectively, leading to problems with blood circulation and temperature control; therefore, symptoms include headaches, feeling dizzy, nauseated, and tired, and muscle cramps,” said Dr. Navin. Dr Yadav added: “These are very common during intense heat and are usually linked to dehydration and heat stress. When the body loses fluids and salts through sweating, your blood pressure can drop, and blood vessels widen due to heat,” said Dr. Yadav.

What are the first signs that my body is not handling the heat properly?

According to Dr. Navin, “Many people do not realise that their symptoms are actually warning signals from the body telling them they cannot cope with the heat, and they tend to disregard these symptoms, believing them to be just an effect of the usual fatigue associated with summer; however, they are usually an indication of imminent heat exhaustion. People who are suffering from heat exhaustion may notice that their skin is very cold, clammy, or sticky, even though the outside temperature is hot.”

How do I know the headaches I get in summer are not migraines?

“Heat is a common trigger for migraines because of dehydration, excessive sweating, poor sleep, bright sunlight, and sudden temperature changes between outdoor heat and air-conditioned spaces. Dehydration and electrolyte imbalance can affect blood vessels and trigger headaches,” said Dr. Chowdhury.

Is it fine if I stay in an air-conditioned room throughout the day to escape the heatwave?

“While many people believe staying indoors or sleeping in an air-conditioned room is enough to escape the effects of heat, the body can still remain stressed after prolonged exposure to high temperatures during the day,” said Dr. Ladhani.

Can AC and heatwaves together damage my eyes?

Dr. Chowdhury said, “Yes, heatwaves combined with prolonged exposure to air conditioning can contribute to eye irritation and dryness. Dehydration during hot weather may reduce moisture in the eyes, while low indoor humidity from air conditioners can worsen dryness further. Symptoms may include dry eyes, redness, burning sensation, and eye strain. These symptoms are often more noticeable in people who spend long hours on screens or wear contact lenses.” “Long-term exposure to air conditioning during heat waves could be a factor in eye discomfort in some individuals. AC can pull moisture out of the air. Symptoms such as itching, redness, and tired eyes can arise from this combination, especially after long periods of screen use,” added Dr. Dhir.

Despite having an AC in the bedroom, I am not getting proper sleep. Does it have anything to do with the heat?

“Yes, very likely. Even with AC, extreme heat can still disrupt sleep quality. High temperatures affect the body’s natural cooling process that helps trigger deep sleep. A few common issues may include the fact that the room may still not be cool enough for your body, and humidity can make the body feel sticky and uncomfortable despite AC,” said Dr. Yadav.

Do any of my medications increase dehydration or heat sensitivity?

“Some medications can put you at risk of dehydration or heat sensitivity as they lead to fluid loss (like diuretics) or reduce your body’s ability to cool itself. Some can also affect electrolyte balance or blood pressure, making you feel weak in the heat. It is necessary to review your medicines, identify any risks, and adjust hydration accordingly,” said Dr. Agarwal.

What is the right time for me to exercise outdoors in this weather?

“You can exercise early morning around 6:00 am to 7:30 am, try going for a morning walk, do yoga, or a gym workout. Don't exercise when there is extreme heat outside, that is from 12:00 pm to 4:00 pm, and stay indoors. You can also exercise after 5:00 pm, try walking, jogging, Zumba, Pilates, or aerobics,” said Dr. Agarwal.

I have kidney disease. How much water should I drink during extreme heat?

Dr. Chowdhury advised, “Those with kidney disease should avoid both dehydration and excessive fluid intake during heatwaves, as either can worsen kidney function. Fluid requirements depend on whether a person is in the early, middle, or later stages of kidney disease. Rather than suddenly increasing water intake, it is better to drink fluids in moderate amounts at regular intervals.” Dr. Dhir added, “People with kidney disease should be particularly cautious about their water intake in extreme heat. How much you get will depend on the stage of your kidney disease, swelling, urine output, and medicines taken.”

I have high blood pressure. How much sodium is safe during hot weather?

“It is important that people with high blood pressure do not consume excessive salt even during extreme summer heat. For most hypertensive patients, a sodium intake of less than 2,000 mg per day is generally recommended unless advised otherwise by their physician. Although sweating leads to some salt loss, routine extra salt intake is usually unnecessary,” said Dr. Chowdhury. Dr Dhir added, “You must also stay away from packaged snacks, pickles, and processed foods. Eat plenty of fresh fruits, vegetables, curd, and home-cooked food to be well-balanced and hydrated.”

Why am I getting acne or heat rash during this heatwave despite the AC?

“Heat rash and acne can still occur indoors during a heatwave. Sweat, humidity, blocked pores, and frequent shifts between outdoor heat and air-conditioned environments can irritate the skin. Air conditioning may also dry out the skin, causing sebaceous glands to produce more oil, which can trigger acne breakouts,” said Dr. Chowdhury. “The sudden transition from hot temperatures outdoors to cooler air indoors can clog sweat glands and trap bacteria, which can lead to acne and heat rash. Wash your face with cool water. Wear loose cotton clothes,” said Dr. Dhir.

How much water should I actually drink during extreme heat?

“There’s no one-size-fits-all number, but during extreme heat, most adults need more fluids than usual because the body loses water rapidly through sweat. On average, aiming for around 2.5 to 3.5 litres a day is reasonable, but if you are outdoors, exercising, travelling, or sweating heavily, your requirement can increase significantly,” said Dr. Yadav.

How do I know if I am well hydrated?

“A good way to judge hydration is that your urine should be pale yellow and not dark, you should not feel excessively thirsty, and if you are sweating a lot. Also, remember that plain water is important, but in excessive heat, electrolytes matter too,” said Dr. Yadav.