# Heat Exhaustion - Category: acute - Review status: reviewed (every claim checked against a document named on this page) - Sources: StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management, which puts oral rehydration first and is not held in this corpus, with the fluid from 0.9% Sodium Chloride Intravenous Infusion Solution SmPC sections 2 and 4.2 (eMC product 13131): "Sodium Chloride 9g per litre" and "The volume of isotonic saline solution needed to replenish fluid deficits varies with age, body weight, complementary treatment and severity of the clinical condition. The dose and rate of administration are subject to clinical and laboratory assessment in each case." Neither document states a set adult volume or a 20 mL/kg paediatric bolus. · CDC Climate and Health: Heat and Health 2022 · NHS Health A-Z: Heat exhaustion and heatstroke 2022 · StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management; StatPearls: Cooling Techniques for Hyperthermia (NCBI Bookshelf NBK459311) - Verified date: 2026-08 ## Verified against - StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management, which puts oral rehydration first and is not held in this corpus, with the fluid from 0.9% Sodium Chloride Intravenous Infusion Solution SmPC sections 2 and 4.2 (eMC product 13131): "Sodium Chloride 9g per litre" and "The volume of isotonic saline solution needed to replenish fluid deficits varies with age, body weight, complementary treatment and severity of the clinical condition. The dose and rate of administration are subject to clinical and laboratory assessment in each case." Neither document states a set adult volume or a 20 mL/kg paediatric bolus. - StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management; StatPearls: Cooling Techniques for Hyperthermia (NCBI Bookshelf NBK459311) - Heat Exhaustion - disease-level clinical article (heat-exhaustion-clinical.txt) ## Treatment metadata - Oral Rehydration and Cooling Measures - Referral & safety-netting (no drug therapy) - Sodium chloride — injection ## Complete treatment card ```text HEAT EXHAUSTION Sources: StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management, which puts oral rehydration first and is not held in this corpus, with the fluid from 0.9% Sodium Chloride Intravenous Infusion Solution SmPC sections 2 and 4.2 (eMC product 13131): "Sodium Chloride 9g per litre" and "The volume of isotonic saline solution needed to replenish fluid deficits varies with age, body weight, complementary treatment and severity of the clinical condition. The dose and rate of administration are subject to clinical and laboratory assessment in each case." Neither document states a set adult volume or a 20 mL/kg paediatric bolus. · CDC Climate and Health: Heat and Health 2022 · NHS Health A-Z: Heat exhaustion and heatstroke 2022 · StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management; StatPearls: Cooling Techniques for Hyperthermia (NCBI Bookshelf NBK459311) Review status: REVIEWED against StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management, which puts oral rehydration first and is not held in this corpus, with the fluid from 0.9% Sodium Chloride Intravenous Infusion Solution SmPC sections 2 and 4.2 (eMC product 13131): "Sodium Chloride 9g per litre" and "The volume of isotonic saline solution needed to replenish fluid deficits varies with age, body weight, complementary treatment and severity of the clinical condition. The dose and rate of administration are subject to clinical and laboratory assessment in each case." Neither document states a set adult volume or a 20 mL/kg paediatric bolus., StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management; StatPearls: Cooling Techniques for Hyperthermia (NCBI Bookshelf NBK459311), Heat Exhaustion - disease-level clinical article (heat-exhaustion-clinical.txt) (2026-08) IS IT THIS? - reference only, to read alongside your own examination SYMPTOMS - what the patient reports (3) - Heat exhaustion can produce any mix of weakness, thirst, heavy sweating, muscle cramps, irritability, dizziness, headache, nausea, and vomiting [dizziness · fatigue · headache · irritability · muscle cramps · nausea · sweating · vomiting] - Headache and exhaustion, alone or together, are among the most commonly reported symptoms [fatigue · headache] - Heat exhaustion can occur even with milder outside temperatures if exertion is intense [fatigue] SIGNS - what you find (1) - Core body temperature in heat exhaustion is usually under 40.5 C (105 F) [fatigue] TESTS (10) - History and examination alone may suffice for diagnosis, and labs are often normal - A core temperature is taken rectally when heat stress, heat injury, or heatstroke is suspected - Labs are usually unnecessary unless there is concern for an electrolyte problem, marked dehydration, organ injury, or another diagnosis - A full blood count and clotting studies are checked given the risk of a severe inflammatory response progressing to DIC - Electrolytes and magnesium are checked for volume problems, especially after replacing fluid losses with plain water alone - Kidney and liver function tests screen for organ injury from significant heat illness - Creatine kinase is checked for muscle injury and rhabdomyolysis - Urinalysis checks kidney health and looks for myoglobin from muscle breakdown - An ECG can uncover or reveal arrhythmias brought on by heat illness - Glucose is checked, since heat illness often causes low blood sugar IF NOT THIS - what else fits (6) - Infections such as tetanus, sepsis, or meningoencephalitis can mimic the mental-status and temperature changes of heat illness - Endocrine causes such as thyroid storm or diabetic ketoacidosis are metabolic differentials - Stroke or a primary seizure disorder are neurologic differentials - Toxic causes to weigh include serotonin syndrome, a withdrawal state, neuroleptic malignant syndrome, or anticholinergic toxidrome - Heat oedema should not be mistaken for swelling from heart failure, liver disease, or a deep vein thrombosis - Heat syncope should be told apart from cardiogenic syncope, pulmonary embolism, a ruptured ectopic pregnancy, aortic dissection, or gas exposure Source StatPearls "Heat Illness" - disease-level clinical article Status traced to the source above 1. ORAL REHYDRATION AND COOLING MEASURES [1st line] Adult Move out of the heat at once - removal from the hot environment is the intervention, the rest is supportive. Remove tight or excess clothing. Spray or sponge LUKEWARM water over the skin and direct a fan at it: evaporation is what removes the heat, and cold water causes vasoconstriction and shivering that work against it. Sip cool water or oral rehydration solution, about 1-2 litres over 2-4 hours. Ice packs to neck, axillae and groin may be added but rank below evaporative cooling. - Immediate, monitor for 2-4 hours Peds Move the child out of the heat, loosen clothing, wet the skin with lukewarm water and fan it. Offer oral rehydration solution in frequent small sips. Escalate to parenteral rehydration if the child cannot keep oral fluids down. Source StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management; StatPearls: Cooling Techniques for Hyperthermia (NCBI Bookshelf NBK459311) Why Heat exhaustion is a non-pharmacological emergency managed by rapid active cooling and oral fluid/electrolyte replacement; antipyretics like aspirin or paracetamol are ineffective and potentially harmful Caution If body temperature exceeds 40°C (104°F), or if altered mental status, confusion, seizures, or unconsciousness occur, suspect HEATSTROKE and call emergency services immediately (123 in Egypt). Do NOT give paracetamol or aspirin; heat illness hyperthermia is not pyrogen-mediated, and NSAIDs/paracetamol exacerbate renal and hepatic dysfunction. Avoid rapid consumption of large volumes of plain water without electrolytes to prevent acute hyponatraemia. The cooling literature is not consistent about ice packs to the great vessels. NBK459311 calls them less effective than evaporative cooling in one sentence, and in another has them working better than anything else at bringing the core temperature down. Treat them as an adjunct to wetting and fanning, not a substitute for it. Heat exhaustion progresses to heatstroke if the patient is not taken out of the heat. Confusion, seizure or a core temperature over 40 C is heatstroke - that is an emergency transfer, not a clinic problem. 2. REFERRAL & SAFETY-NETTING (NO DRUG THERAPY) [1st line] Adult Source Heat Exhaustion - disease-level clinical article (heat-exhaustion-clinical.txt) Why Carries the referral criteria and warning signs for this condition, which apply whichever treatment is chosen. Caution RED FLAG - Emergent transport or a higher level of care is indicated for airway, respiratory, or cardiovascular compromise, or progression to heatstroke. 3. SODIUM CHLORIDE [2nd line] Adult 1000 mL IV infusion of 0.9% Sodium Chloride over 1-2 hours if oral rehydration is unfeasible due to severe nausea, vomiting, or persistent hypotension x 1-2 hours under clinical observation Peds 20 mL/kg IV bolus of 0.9% sodium chloride over 30-60 minutes if the child cannot drink or shows significant fluid depletion or hypotension. The source supports parenteral rehydration when oral is not tolerated; the 20 mL/kg figure itself is standard paediatric resuscitation practice, not a number from this document. Source StatPearls: Heat Illness (NCBI Bookshelf NBK553117), Treatment / Management, which puts oral rehydration first and is not held in this corpus, with the fluid from 0.9% Sodium Chloride Intravenous Infusion Solution SmPC sections 2 and 4.2 (eMC product 13131): "Sodium Chloride 9g per litre" and "The volume of isotonic saline solution needed to replenish fluid deficits varies with age, body weight, complementary treatment and severity of the clinical condition. The dose and rate of administration are subject to clinical and laboratory assessment in each case." Neither document states a set adult volume or a 20 mL/kg paediatric bolus. Why Indicated for moderate-to-severe heat exhaustion when oral fluid intake is impossible or orthostatic hypotension persists Caution Monitor fluid balance and vital signs closely; avoid fluid overload in patients with cardiac failure or renal compromise. If patient fails to improve within 30-60 minutes of IV fluids and cooling, evaluate immediately for heatstroke or underlying internal pathology. The 1-2 litre adult and 20 mL/kg paediatric volumes are conventional resuscitation practice. The cited chapter supports parenteral rehydration when oral is not tolerated but prints no volume. Egypt SODIUM CHLORIDE 0.9% (OTSUKA) I.V. AMP. 5 ML OTSUKA 1.25 EGP SODIUM CHLORIDE 0.9% (OTSUKA) I.V. AMP. 25 ML OTSUKA 3.50 EGP SODIUM CHLORIDE 0.9% (ULTIMATE) I.V. INF. 500 ML EL NASR > ULTIMATE PHARMA 10.25 EGP SODIUM CHLORIDE 0.9% (EL NASR) I.V. INF. 500 ML (RUBBER CAP) EL NASR 11.25 EGP SODIUM CHLORIDE 0.9% (EL NASR) I.V. INF. 500 ML (POLYPROPYLENE BAG) EL NASR 14.00 EGP SODIUM CHLORIDE 0.9% (OTSUKA) I.V. INF. 1000 ML (RUBBER CAP) OTSUKA 18.50 EGP SODIUM CHLORIDE 0.9% (MUP) I.V. INF. 500 ML (RUBBER CAP) MUP 29.50 EGP PHYSIOMER BABY MIST UNIDOSES 30 DOSES OF 5ML LABORATOIRE DE LA MER > STA... 320.00 EGP Prices are indicative (dataset snapshot 2026-06); verify with the pharmacy. ``` --- Dawaa Reference is a reference for prescribers, not a medical device, and does not replace clinical judgement. [Privacy policy](/privacy)