Chihuahuas are known for being very graceful and alert dogs. They are full of energy and often times look like they have a very saucy expression. Often times, they can become extreme barkers unless they are well-trained to stop on command. They need to be with a loving and patient human being who will pamper them and train them well. They are extremely devoted to their humans.
The personality of the human can have a huge impact on the personality of the Chihuahua. If not trained properly, Chihuahuas often suffer from small dog syndrome and an easily be provoked to attack. This is especially important to keep in mind when putting a Chihuahua in a home with small children. The children need to be trained to be patient and calm with the dog.
Chihuahuas sometimes are prone to genetic abnormalities, often neurological ones, such as epilepsy and seizure disorders so it is very important to keep them under the regular care of veterinarians to monitor their health. They are also, just like many other toy breeds, prone to hydrocephalus, which is when a puppy has an abnormally large head during the first months of life.