Vomiting and diarrhoea are signs that your dog could be unwell. An animal may vomit for many reasons other than being ill, such as if they have swallowed something they shouldn’t have. Diarrhoea could be the result of a change in diet, an allergic reaction or stress, or something more serious such as kidney or liver disease. A change in temperament could also mean your dog is ill, for instance, if they switch from a friendly pet that loves company to being irritable and isolated. Any unusual behaviour such as panting, excessive lip licking or aggression could be signs of illness. Lethargy and lack of activity also indicate that your dog is unwell. If your usually active dog seems to be spending more time lying down instead of playing with you, there will be a reason. A dog’s inability to tell their owners exactly how they feel can often be vocalised in other ways, if your dog whines, whimpers, cries or barks more frequently, or at unusual times of the day, they could be trying to tell you they are ill or in pain. Another sign that something isn’t right is your dog urinating more or less frequently than usual. Changes in weight, such as weight loss or gain, as well as bad breath, could also be a sign of dental problems or gum disease, digestive or respiratory problems, as well as many other ailments.