Chihuahuas are perhaps best known for their tiny size, generally weighing no more than 6 pounds. However, they're also known for shivering or shaking more often than other breeds of dog. This can be due to the cold, but it can also be caused by various other factors, most of which are harmless. Don't be too alarmed if your Chihuahua shivers, but do seek professional advice.
While Chihuahuas are fairly likely to shiver and it usually isn't a symptom of a more serious condition, shivering in dogs can be caused by underlying medical issues. Therefore, it's a good idea to take your Chi to the vet, just to be safe, especially if he hasn't shivered much in the past. Possible medical causes of shivering include poisoning, pain, nausea, distemper and generalized terror syndromes.
Shivering in Chihuahuas can simply be caused by excessive excitement. They have a tendency to be highly strung, so it doesn't take much to push their excitement over the edge. If you notice your pooch shivering when you've just come through the door or it's time for walkies, then it's likely to be caused by excitement. While this isn't dangerous for your dog, you can minimize excitement by staying calm and keeping greetings brief.
Another possible reason why your Chihuahua is shivering is due to anxiety. Anxiety in dogs can be caused by a variety of factors, such as loneliness, isolation, lack of physical or mental stimulation, or a change in circumstances. If you can identify the cause of your canine companion's anxiety, try to remove the stressor from his life to resolve the problem. If you can't find out why your pup is anxious, take him to see a veterinarian.
Shivering can also be a sign that your Chihuahua is afraid. Although they're often confident dogs, you must remember that they're very small, so the world around them can seem intimidating. Make sure that your Chi doesn't become afraid of you by treating him gently and always using positive reinforcement methods when training him, rather than punishing or scolding him. He could also become fearful of larger pets in the house, so keep an eye on any interactions to ensure he's not being bullied.