Since dogs cannot sweat profusely like people can, panting is the main way a dog can cool off and help regulate its body temperature. Although dog panting is normal after exercise or when the weather is warm, panting to the point of hyperventilating needs medical attention. A dog that suddenly pants heavily could be in pain or severely frightened, so the condition should be addressed immediately.
Check for signs of heat stroke. Brachycephalic dogs, or dogs with short noses like pugs or bulldogs, are more prone to heat stroke than dogs with long noses, according to Mar Vista Animal Medical Center. Brachycephalic dogs may succumb to heat exposure even after mild exercise on a humid day, so they always need supervision when exercising. Other signs of heat stroke include extreme drooling or slobbering and sudden collapse. Get such dogs into a cool spot, cover them with a wet towel and take them to a veterinarian immediately.
Check for other symptoms of health problems. Since dogs pant when in pain, check for vomiting, diarrhoea, distended abdomen, swelling, lameness or a seeming inability to lie down comfortably. Panting far more rapidly than usual accompanied with sudden lethargy, coughing and refusing to eat may be signs of heart failure, pneumonia or lung cancer, according to "The Veterinarian's Guide to Your Dog's Symptoms." The dog will need to see a veterinarian.
Check for signs of fear. If the dog does not seem to have any other medical problem and is not showing any signs of heat stroke, the dog could be frightened. Dogs afraid of thunderstorms pant heavily, walk with a crouch and sometimes try to jump onto an owner's lap for safety. Dogs may also pant in fear if they have just been yelled at for misbehaving.
Get to know your dog's normal panting behaviours. If the dog normally pants a few minutes after a walk or romping in the yard, then no veterinary assistance is needed. But if the dog pants for hours or pants during times when it normally does not pant, this could be the sign of a health problem. Call a veterinarian as soon as possible.
Larger dogs tend to pant more often than smaller dogs, according to "The Dog Bible: Everything Your Dog Wants You to Know." Pregnant female dogs often pant heavily when contractions begin.
Never ignore a dog that pants abnormally or pants and had other symptoms.