During the dog days of summer, high temperatures and humidity levels can be uncomfortable for people—and dangerous for your pet. Dogs have a higher average body temperature than humans and cannot tolerate the heat as well as we can. It’s important to never keep your dog confined in a car (even with the windows open) during warm weather, or outside without access to shade. Pets left in excessive heat may develop a serious, life-threatening condition called heatstroke, or hyperthermia. The most common signs are restlessness or agitation with vigorous panting. You may also see diarrhea, vomiting, and blue or bright-red gums.

If you see these signs immediately move your pet to a cooler location (in front of a fan, if available) and bring him to the veterinarian. On the way, you can place cool (not cold) water on his stomach. Note: Never use ice-cold water or put your pet in an ice bath. A drastic change in temperature can be very dangerous.

Your veterinarian may need to administer intravenous fluids and/or sedatives to help your dog recover and may need to run tests to determine if heatstroke has cause damage to internal organs.

Get tips on helping your dog beat the heat here. 

And see this dog's clever way of staying cool here.