Heatstroke is a serious and often life-threatening condition dogs are susceptible to whenever the weather becomes hot and humid. Dogs cannot sweat; therefore, they do not efficiently handle heat stress. They exchange heat mostly through panting. Heatstroke is most common in large breed dogs, overweight dogs and dogs with short noses.
The most common clinical signs of heatstroke are weakness, loss of balance, excessive panting, increased salivation, loud or roaring breath sounds, mental dullness, collapse and death. Body temperatures over 106 degrees Fahrenheit are a critical emergency and require immediate treatment. As body temperatures go above 107 degrees Fahrenheit, organ damage occurs, shock and cardiovascular collapse ensues, brain swelling and disseminated intravascular coagulation (DIC) are common complications that result from heatstroke. If the body temperature goes above 109 degrees Fahrenheit, the prognosis becomes very poor.
Death from heatstroke can occur fairly quickly. It can be as short as 20 minutes, as in a “closed car” situation. It is more common for dogs to experience heatstroke in the first few days of warm weather when they are becoming acclimated to the heat and for it to occur in conjunction with exercise or excitement. Heatstroke may occur within an hour or more under these circumstances, but could develop more quickly if the pet was already struggling with the heat prior to exercise.