India is witnessing a dangerous rise in extreme heat events. Heatwaves that were once seasonal and short-lived are now becoming more frequent, prolonged, and intense. As a doctor, I have observed that heat-related illnesses, especially heat stroke, are no longer rare emergencies but an increasing public health concern affecting urban and rural populations alike.

Heat stroke is the most severe form of heat-related illness. It occurs when the body’s temperature regulation fails and the core body temperature rises above 40°C. This condition can rapidly damage the brain, heart, kidneys, and muscles, and may become fatal if not treated immediately.

Common symptoms include:

  • High body temperature
  • Hot, dry skin or excessive sweating
  • Severe headache
    Dizziness and confusion
  • Rapid pulse
  • Vomiting
  • Loss of consciousness or seizures

The rise in heat stroke cases in India is closely linked to climate change. Global warming has increased the frequency and severity of heatwaves across the country. According to the World Health Organization (WHO), heat exposure is increasing worldwide due to climate change, with Asia carrying a major burden of heat-related mortality.

India is particularly vulnerable because of:

  • Dense population
  • Rapid urbanization
  • Poor housing and ventilation
  • Outdoor labor workforce
  • Limited access to cooling systems
  • Urban heat island effect

Recent years have seen temperatures crossing 50°C in some parts of northern India. Reports have documented thousands of suspected heat stroke cases during severe heatwave periods.

Climate change does not only increase temperature; it also increases humidity. High humidity prevents sweat evaporation, making it harder for the body to cool itself. Studies suggest that humid or “oppressive” heatwaves may become more common in India and are strongly associated with higher mortality.

The most vulnerable groups include:

  • Elderly individuals
  • Children
  • Pregnant women
  • Patients with diabetes, hypertension, heart disease, or kidney disease
  • Outdoor workers such as laborers, farmers, traffic police, and street vendors

Heatwaves also burden healthcare systems. Hospitals across India are increasingly preparing dedicated heat stroke wards, cooling facilities, IV fluid supplies, and emergency response protocols during summer months.

Prevention remains the most effective strategy. The following measures can significantly reduce heat-related illness:

  • Drink adequate water and oral rehydration solutions
  • Avoid direct sun exposure during peak afternoon hours
  • Wear light-colored loose cotton clothing
  • Use hats, umbrellas, and cooling measures
  • Avoid strenuous outdoor activities in extreme heat
  • Ensure proper ventilation at home and workplaces
  • Never leave children or elderly persons inside parked vehicles

At the community and policy level, India urgently needs:

  • Climate-resilient healthcare systems
  • Early heatwave warning systems
  • Public awareness campaigns
  • Urban greening and tree plantation
  • Heat action plans in all cities
  • Protection policies for outdoor workers

Climate change is no longer a distant environmental issue; it is a direct medical emergency affecting millions. Heat stroke represents one of the clearest examples of how environmental changes are impacting human health today. As healthcare professionals, policymakers, and citizens, collective action is essential to reduce the health burden of rising temperatures and protect vulnerable populations in India.

Dr. Prakash Agarwal

MBBS, FIM (Internal Medicine)

Consultant Physician