Dogs have very few sweat glands and only excrete a little heat from the pads of their paws. Panting is how dogs release heat from their body. However, there are other reasons a dog could be panting that have nothing to do with the temperature. Always make sure the dog has plenty of water and access to a cool, shady place on hot days. If it still seem to be panting excessively then the dog should be seen by a veterinarian to rule out any health problems.
Dogs will pant when they are excited, stressed or scared. Visits to the vet, car rides and new experiences can make your dog pant. Fear can also bring this response in dogs. A new situation can cause anxiety and panting until the dog calms down again. Reassure your dog with gentle words and petting to help reduce the level of excitement, fear or anxiety they may be feeling.
When the dog is well exercised this will induce panting. Dogs naturally pace themselves and will know when to rest. After engaging in any physical activity with a dog, offer it water to help bring its body temperature down. The panting should slow down as its body adjusts.
Pain and Illness
If the dog is sick, injured or having other health problems it may begin to pant excessively. Heart problems, infections, fever, Cushing's syndrome (adrenal issues) and respiratory issues can cause a dog to pant. If you notice your dog has been panting excessively, call your veterinarian. Depending on the cause of the problem, the veterinarian may prescribe medication to help the dog heal or rest more comfortably. Pain can also cause a dog to pant. Injuries that are not visible can cause pain for the dog. The dog will try to manage the pain by panting.
If the dog is taking any medication and suddenly seems to be panting a lot check with your veterinarian. Panting can be a sign the medication needs to be adjusted. Call the veterinarian as soon as possible. Adjusting the dosage or changing the medication might stop the excessive panting and help the dog rest more comfortably.
Older dogs naturally pant more than their younger counterparts, but it's also a sign of congestive heart failure. Pain from arthritis or other joint issues can also cause the dog to pant. If you notice excessive panting, let the veterinarian to rule out any health issues that your senior dog may be experiencing.