The Chihuahua is the smallest breed of dog in the world, weighing approximately 6 lbs. or less. The Chihuahua is a popular toy breed and it can live for up to 15 years or more. Unfortunately, the Chihuahua―like many purebred dogs―isn't without his health problems. Symptoms of kidney failure may begin to show up in Chihuahuas around 10 to 14 years of age.
The kidneys are an important part of the canine urinary tract, so many of the symptoms of kidney failure include various changes in urination. For example, the affected Chihuahua may be producing more urine and he may also be urinating more frequently than usual; however, some dogs with kidney failure may produce little or no urine whatsoever.
Dogs affected by kidney failure, increased urine production and frequency may also display signs of increased thirst, such as excessive drinking.
With kidney failure, the dog's body is attempting to compensate for the kidney's loss of function by pushing more water through the body in order to remove toxins that are building up. Unfortunately, this often leads to dehydration. Signs of dehydration in canines include loss of skin elasticity, dry gums, sunken eyes and slowed capillary refill time.
Some Chihuahuas with kidney failure may also experience diarrhea, which will also contribute to dehydration.
Canine renal (kidney) failure may also cause changes in behavior such as depression or lethargy. These behavioral changes may vary in severity from Chihuahua to Chihuahua, though not all dogs will experience these changes.
Vomiting is another symptom of kidney failure in a dog, though it can also signify many other canine health issues. While occasional vomiting should not cause concern for an owner, vomiting that is abnormal or excessive requires a trip to the veterinarian.
Halitosis, or bad breath, is also a sign of kidney failure in a Chihuahua.
Some dogs may experience weakness of the muscles. Weakness can vary in severity and for some, weakness may become so extreme that the dog refuses to move; or the muscle tissue begins to waste away.
Loss of Appetite and Changes in Weight
Kidney failure may cause some dogs to refuse to eat for more than one day. In some cases, the dog may become anorectic. Any weight changes, especially in small toy breeds like the Chihuahua, require immediate veterinary attention.
Loss of Coordination
In some cases, kidney failure can cause the affected Chihuahua to suffer from loss of coordination when walking.