Dogs have evolved alongside humans for the past ten thousand years and accordingly are pretty good at communicating with us when they are not feeling well.  Dogs can get sick from many, many things – but generally speaking, the signs are pretty universal.


When a dog is feeling sick, he will have less energy than normal. It’s where the phrase ‘looking hang dog’ came from: sick dogs will mope, flop around, not want to play, and sleep more than usual.

Changes in Appetite and Weight

A dog that is sick will usually eat less than normal and lose weight, but some diseases, such as cushings disease, will have an increased appetite, and dogs with cushings disease or hypothyroidism will  gain weight.

Vomiting or Diarrhea

Vomiting and diarrhea are sure signs that your pet is sick. The problem can either be primarily with the intestinal tract (such as an obstruction or parasite) or it can be a separate system wreaking havoc and causing the signs, such as an infected uterus causing vomiting or diabetes causing diarrhea.

Changes in Drinking and Urinating

Increases in water consumption or urination are signs that your dog needs veterinary attention. Diseases ranging from urinary tract infections, to hormonal conditions, to kidney disease can cause your dog to drink more than usual. In these cases, it is a good idea to bring a urine sample to the veterinary hospital for testing.

Excessive Licking, Scratching or Hair Loss

The skin is the largest organ in the body and is exposed to all sorts of insults. Dogs can get parasites and skin infections that lead to itching and hair loss. Problem inside the body, like hormonal or autoimmune disorders, can also cause changes in the skin.

Bad Breath

While bad breath is usually a sign of dental disease, bad breath can also happen with stomach ulcers or kidney disease. If your dog’s breath is worse than normal, or there is any drooling, schedule a checkup.

Coughing and Sneezing

Dogs can get heart disease, bronchitis, pneumonia, tracheal disorders, allergies and other nasal problems just like humans. If you notice coughing or sneezing, get your dog checked out.


If your dog has a bone or joint problem, the most obvious sign you will see is limping or holding a leg up. This can be a sign of a joint disorder, such as a ruptured ligament or arthritis, a skin disorder, such as a lacerated or abraded paw pad or torn toenail, or a primary bone problem, such as bone cancer. Limping is a sure sign that your dog needs a physical exam and probably an x-ray, and don’t be surprised if your dog stops limping when you get to the veterinary hospital.  It’s common that most dogs get keyed up on adrenaline when they go to the vet, and that masks the pain they are feeling.