Heat Exhaustion and Heat Stroke

Overview

Heat-related illness ranges from heat exhaustion (mild — heavy sweating, weakness, dizziness) to heat stroke (severe — body temperature >40°C, confusion, seizures, loss of consciousness). Heat stroke is a medical emergency causing permanent brain damage or death if untreated. Neurological symptoms occur because heat reduces cerebral blood flow and causes direct thermal injury to neurons.

Symptoms

• Heavy sweating
• Weakness and fatigue
• Dizziness and headache
• Nausea and vomiting
• Confusion and disorientation
• Seizures
• Loss of consciousness
• Hot dry skin (heat stroke)

Causes

• High ambient temperature and humidity
• Dehydration
• Prolonged exertion in heat
• Certain medications (diuretics, antihypertensives, psychiatric drugs)
• Age extremes (elderly, infants)
• Chronic illness (heart, kidney, neurological conditions)

Risk factors

• Age >65 or <5
• Chronic illness
• Medications affecting thermoregulation
• Prolonged heat exposure
• Poor hydration

Diagnosis

Clinical diagnosis based on temperature and symptoms|Core body temperature measurement|Neurological examination for altered consciousness|Exclusion of other causes

Treatment & management

Immediate cooling (cold water immersion, ice packs, fans)|IV fluids for dehydration|Benzodiazepines for seizures|Hospital admission for heat stroke|Treat underlying cause

Management is individualized and discussed with benefits, limitations, and follow-up.

Prevention & self-care

Hydration (drink regularly, don't wait for thirst)|Avoid peak heat hours|Light clothing|Acclimatization to heat|Monitor vulnerable individuals

When to seek medical attention

• Confusion, disorientation or altered consciousness
• Seizures
• Loss of consciousness
• Inability to drink fluids
• Symptoms persisting despite cooling

Frequently asked questions