Inappropriate Mouthing

Inappropriate mouthing (also called nipping or “play biting”) is a common unwanted behavior in adolescent and adult dogs. Several things can prompt a dog to become mouthy, such as arousal, conflict, inappropriate play or a history of being rewarded for the behavior (often unintentionally). Inappropriate mouthing may start with soft bites and nips at a person’s hands or feet, but it can escalate to jumping and grabbing at clothes and/or body parts—sometimes resulting in torn clothing and bruises. It’s important to recognize the signs that the behavior might be about to occur, and to manage and modify the behavior quickly and appropriately.

Potential Indicators for Unwanted Mouthing

While the following behaviors are common signs that mouthing may occur, this list is not meant to be exhaustive. Every dog is an individual and may have different behaviors they display before they start mouthing. Commonly seen signs may include:

  • Dilated pupils
  • Repeated jumping
  • Piloerection (raised fur on the shoulders, back and tail)
  • Body checking (bumping or throwing body against people or objects)
  • Leash tugging or grabbing
  • Staring at or targeting body parts or clothing
  • Panting
  • Difficulty paying attention OR hyper-focus on a person, animal or object


Management is an important tool that helps prevent the dog from mouthing you during times you can’t actively train them. Good management techniques will mean your dog doesn’t get to practice the unwanted behavior, which will make it easier to teach your dog not to do those behaviors! Management techniques may include no-go zones, crates, and draglines.

Click each technique below to learn more information.

No-Go Zones 

These are spaces where the dog can be physically separated from you with a barrier so that they are unable to mouth you. One barrier option is to install a gate. Look for a gate that is tall enough that the dog cannot jump over it, that can be pressure mounted or installed into the wall, and that securely shuts. 


The crate should at least be large enough for the dog to stand up, turn around and lie down without their body touching the sides, but it can also be larger! The crate should never be used for long-term confinement. See more about crate training your dog.

Drag lines 

A drag line is simply a lightweight leash that you can attach to your dog’s harness or collar and let drag as the dog moves about your home or enclosed yard. Only use a drag line when someone is able to supervise the dog. If the dog begins mouthing, grab the drag line and use it to hold the dog away from you long enough to redirect the behavior or move the dog to a management place, like the no-go zone or a crate. When holding the line away from you, stand still and hold the drag line up and away from you, with your arms straight out in a T-shape.

Please note that before using either a no-go zone or a crate to manage mouthiness, you will need to teach your dog that going behind the gate or into the crate means good things. Practice having the dog go inside their no-go zone or crate when they’re calm and provide them with an enrichment item, like a stuffed Kong toy or bully stick, to enjoy while there. 


Training and management are both important pieces of the puzzle when addressing unwanted behavior. While management helps prevent a behavior from occurring in the moment, training involves actively teaching your dog an alternate behavior to perform in the place of mouthing. 


The longer the dog engages in the behavior, the more excited they become and the harder it is for them to calm down. Calmly interrupt when you see any of the warning signs listed above. You may choose to interrupt with a short “uh oh!” or by tossing a handful of treats on the ground, which focuses the dog’s attention on the ground instead of on you. Sniffing for treats has the added bonus of helping your dog calm down. When interrupting your dog, stay as calm as possible. Raising your voice or making big motions with your arms can often excite a dog more.


Relying solely on interrupting behaviors and telling our dogs “no,” doesn’t tell the dog what we want them to do. Dogs will often replace mouthing with another behavior that may be appropriate for dogs but not for people. Instead, teach your dog to respond to their name and to cues like sit, lay down and grab a toy. 

When your dog is behaving in an unwanted way, first get their attention by saying their name and then redirect them to do a behavior that will make mouthing difficult. For example, if your dog is sitting they are not able to jump up and mouth you! Sitting or lying down has the added benefit of helping your dog calm down. It is likely you will need to reward the behavior with a tasty treat. Repeated enough times, the dog will begin to understand that the undesirable behavior does not get them what they want, but the new behavior does.

Reward Polite Behavior 

It’s easy to focus on undesirable behaviors when they occur and forget to reward the behaviors that we do want our dogs to do. Every moment with your dog is a moment you can use to help teach them desired behaviors. You can reward your dog with attention, play, or food. Choose whatever your dog enjoys the most, though food is usually the preferred reward. The more often you reward your dog for behaving politely or calmly, the more often they’ll engage in this behavior! 

Avoid punishing your dog for unwanted behaviors. For many dogs, any attention is good attention. If your dog is jumping up on you and/or mouthing you to try to get you to interact with them, even scolding or otherwise reprimanding your dog can make the behavior more likely because it’s still attention.

Time outs

If your dog repeatedly mouths you despite your redirection attempts, direct your dog to their crate or no-go zone. It’s important that your response is immediate and consistent: inappropriate behavior should always and immediately result in losing access to you. Once they’re calm, they can come back out, but if they start the behavior again, they should lose access to you again.

Helpful Tips

Set yourself up for success!

  • Wear a treat pouch to ensure quick and consistent rewarding of polite behaviors until the new behavior is strongly established and the old behavior is starting to go away.  Once the new behaviors are established, transition from the treat pouch to treat stations located in strategic places around your home that are easily accessible to humans but not to dogs.
  • Behavior doesn’t change overnight! For however long your dog has been displaying these behaviors, it can take just as long for the behaviors to reduce. The key is to be consistent and clear about what behaviors you’re rewarding.
  • Make sure you are meeting all of your dog’s needs. Mental and physical exercise are both equally important. All dogs need some form of both daily and every dog is different in how much they need. Some dogs only need a brisk walk, others need a five-mile run! Mental exercise can be provided by engaging in training games or by providing interactive toys daily

If you do not make progress with the above tips, we recommend hiring a certified professional dog trainer or consulting with a board-certified veterinary behaviorist. See more information on locating a behavior professional near you.

Still have questions?

Contact our Behavior Specialists at [email protected] or (212) 876-7700 ext. 4971

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