Panting can sometimes give you a clue that your dog is in pain. If your dog keeps panting for no apparent reason, and this is accompanied by other signs of discomfort, such as excessive self-licking, enlarged pupils, restlessness or whimpering, talk to your vet.
Certain illnesses, like Cushing’s disease or heart problems, can make your dog pant more than normal. If increased panting is combined with other symptoms like lethargy, coughing or increased urination, then book your dog into the vet for a check-up as soon as possible.
The sudden onset of unexplained, heavy panting can also be a sign that your dog has eaten something poisonous. In mother dogs that are nursing, heavy panting can be a sign of milk fever, also known as eclampsia. As with any abrupt and acute deterioration in their health, seek veterinary advice immediately.