Why Do Chihuahuas Bite



Roxy is a small dog. She is tiny in size but loud in personality. In fact, there is nothing that can stop Roxy from conquering the world she lives in. She is mighty in her ways and will even act a bit aggressive if things are not going right. Although Roxy seems like an innocent Chihuahua, she can become scary in a moment’s time like a crocodile when it snaps at its prey. Yet, this tendency is not the Roxy you know and now you want to understand and discover why Roxy has a need to bite those around her.

The Root of the Behavior

Chihuahuas are mighty canines. Although their bodies appear tiny, their hearts are quite large. In fact, Chihuahuas were bred to be small and loving companions that always remain with their owner, which means that this type of dog is not naturally aggressive! If your Chihuahua bites you, then there is a valid reason for it. Sometimes, small dogs will bite because they have something called small dog syndrome. Small dog syndrome is when smaller dogs begin to growl, bark, bite, and even become possessive over their things. Roxy is probably snapping at you because she is trying to claim her spot in the world. Yet, as Roxy’s owner, you have availability to every resource there is to help her out. Biting is always a defense mechanism, which means that your dog is trying to communicate her needs in an aggressive way. For example, Roxy may try to bite at you when you go to take her dog bowl away because, in the past, you may have taken her bowl away before she was finished with her meal. 

Your Chihuahua may also bite because of pain-induced aggression or maternal aggression. If your Chihuahua is in pain, she may become more aggressive than normal and bite the nearest person or animal in sight. Sometimes, Chihuahuas will do this when you touch their knee if they have the medical condition patellar luxation. If your dog has maternal aggression, their hormones may be causing the aggression. When a dog gives birth, oxytocin is released from the hypothalamus, which stimulates contractions during labor. Prolactin production will then increase, stimulating milk production. These hormonal changes are known to affect your dog’s maternal instinct, raising aggression rates in your Chihuahua. It is suggested that you train your puppy during the proper growth phases of 4-12 weeks and 7-8 months. You can set proper rules and boundaries for them to follow. You also want to listen to your dog’s needs and treat them with respect, despite their small size. This will keep your dog happy, calm, and loyal just as your dog was meant to be. 

Encouraging the Behavior

Although Roxy may feel threatened, you are not going to want to allow her to assert her dominance by biting you or anyone else. If Roxy has fear, pain, or acts in a territorial way, you are going to want to help her and train her. It is important to set boundaries and rules for your Chihuahua so they communicate their needs in a proper way. For example, you are not going to want Roxy to chase your mailman when he comes to deliver mail at your house. You need to teach Roxy that this is your property and as the alpha leader, you will protect it. 

Sometimes, illness can also contribute to aggression. Hypothyroidism and Lyme disease are common illnesses in Chihuahuas that can increase levels of aggression. If it appears that your dog is sick, you will want to talk to your veterinarian and help your dog heal. This can decrease their aggression levels. First, decide why your dog is acting out and then help your Chihuahua get rid of their biting habit. You may also want to socialize your Chihuahua to the world they live in. This will help them become accustom to human habits and rules that are in place. Once your dog feels respected and learns how to communicate properly, aggression will not be as big of an issue. 

Other Solutions and Considerations

If your Chihuahua has a tendency to bite, you want to discover why your dog is acting out because there are many different solutions to your dog's biting habit. From socialization to healing their body, your dog's biting tendency may stop if you provide your dog with what they need. Spaying and neutering can also be a helpful solution to your dog's biting habit. Aggression is shown to reduce by 60% in males and by 35% in females with spaying and neutering. The lower levels of testosterone reduce hyperactivity, fear, and aggression and the reduction of the female heat cycle reduces any behaviors that occur when your dog is in heat. If you feel like you need additional help, you can contact your veterinarian or hire a behavioral specialist for your dog.


Despite their small size, Chihuahuas have bold personalities. They want to be loved and appreciated for all that they do and as pet owners, we have the power to help our dogs thrive. Yet, we must make sure they know that we are their leaders and as their leaders, all we want to do is provide them with love, support, and respect during all of their days.