Dogs cannot sweat effectively—they rely on panting to dissipate heat. When ambient temperature exceeds their ability to cool, core temperature rises rapidly. Body temperature >106°F (41°C) causes cellular damage; >109°F can be fatal. Brachycephalic breeds (Bulldogs, Pugs) are at highest risk. Use the Triage/Emergency Specialist and Vital Signs Reference for guidance.
Signs: excessive panting, drooling, bright red gums, lethargy, collapse, vomiting, diarrhea, seizures. Rectal temperature >104°F (40°C) indicates heat stress; >106°F is heat stroke. Progression to DIC, renal failure, and cerebral edema can occur hours later.
Risk factors: brachycephalic anatomy, obesity, exercise in heat, confined in car, lack of shade/water.
Warning: Never leave a dog in a car, even with windows cracked. Interior temperature can reach 120°F within minutes. This is the leading cause of preventable heat stroke.
Move to Shade
Get the dog out of heat immediately.
Cool Gradually
Apply cool (not ice-cold) water to body, especially groin and armpits. Use fans. Avoid ice—it causes vasoconstriction and can slow cooling.
Offer Water
Small amounts if conscious and swallowing. Do not force.
Transport to Vet
Continue cooling during transport. Stop active cooling when temp reaches 103°F to avoid hypothermia.
Veterinary treatment includes IV fluids, active cooling (until 103°F), oxygen, and monitoring for DIC, renal failure, and neurologic sequelae. Hospitalization for 24-48 hours is often needed.
- Heat stroke: temp >106°F; brachycephalic breeds at highest risk.
- First aid: shade, cool water, fans; avoid ice. Transport to vet.
- Stop cooling at 103°F to prevent hypothermia.
- Never leave dogs in cars—leading preventable cause.
- Prevention: avoid exercise in heat, provide shade and water.