Sudden Aggression in Dogs

When your friendly and easy-going dog suddenly attacks another dog, child or you, it’s an extremely terrifying and confusing moment. Many pet owners wonder what exactly caused their dog to growl, snap or bite. The answer isn’t always clear. One thing’s for sure is if you witness sudden aggression in your dog, you need to address it immediately.

Why is My Dog Suddenly Aggressive?

We all want to understand why our dogs suddenly become aggressive because if we can identify the cause, we can fix it. Sometimes, the cause of aggression in dogs is pretty obvious and other times we have to dig deep to find the real reason our dogs acted out. Below are a few reasons on why a dog may suddenly growl, snap, lunge or bite. If you’re still unsure of the cause, partner with a dog trainer and veterinary behaviorist to resolve this bad dog behavior.

Please remember: Never allow children (or anyone, really) to sit on, ride, tease, pinch, pull, poke at any part of a dog’s body, roughly pet, throw something at, run toward, hit, scream, kick or step on a dog. Doing this will certainly cause pain or scare a dog, which will cause aggression.

Pain

Dogs are stoic creatures. It’s unbelievable how dogs can mask excruciating pain. When dogs are in pain, they’ll growl, snap or bite if you touch a painful area; it hurts! On the other hand, if your dog hides, constantly pants, drools, limps, licks a specific area, whines when moving or remains still, he’s likely in pain as well. If you suspect your dog is suffering, bring your dog to a veterinarian immediately. Then, conduct a family meeting to explain that physical petting and cuddling your dog is painful for him now, so give your dog space until he feels better.

Scared

Dogs get scared more than their pet owners know. Many dogs are frightened when a new person touches them, visits their home, yells at them, physically hurts or punishes them (i.e. hitting, collar correcting, pushing) and so forth.

For professional dog trainers, it’s pretty easy to know when dogs are scared. You’ll notice a dog is scared when his body language changes quickly, ears flatten back, tail tucks, eyes widen, and body stops moving and freezes or leans away from whatever is scaring him.

Some dogs will even growl, which may translate to “please leave me alone,” “stop doing that,” “this is freaking me out,” “if you don’t stop, I will run away or hurt you,” or “I’m scared.” Always listen and respect your dog’s growl. If you punish or ignore a dog for growling, your dog will escalate his warning to an air snap or bite. When your dog growls, he’s begging you to stop scaring him.

Resource Guarding

Dogs love their resources. They love toys, food in their bowl, chewies, treats, cozy spaces and even their pet owners. Some dogs will guard their resources fiercely. You can see this in action when you walk next to or touch your dog’s beloved resources. You’ll notice your dog will either hover over the item, freeze, growl, snap or bite.

In the dog training world, we call this resource guarding. Do know, resource guarding is a completely normal dog behavior. Those that guard their resources survive. Although it can be scary if resource guarding occurs in your home, especially around other dogs and small children.

RELATED: My Dog Steals Food From Children

Never punish your dog for resource guarding. You’ll make the situation much worse. Instead, teach your dog or puppy that trading his favorite items for super yummy treats is rewarding. Check out additional details on eliminating resource guarding behavior.

Personality

This one is usually a shocker. Many pet owners either refuse to accept their dogs aren’t friendly or completely misread their dog’s behavior. Once, many years ago, a pet owner insisted I hold her growling small dog during a behavior consult. This 8-lb dog was firmly nestled in his pet owner’s arms and as the owner approached me, her dog growled, flashed his teeth and sneezed/snorted. Of course, I backed away, but the pet owner insisted her dog was only “smiling” at me.

Long story short, we had a discussion on interpreting her dog’s body language, which completely stopped all of her dog aggression issues. If only all consults were that easy. 🙂

Here’s the truth: many dogs just don’t like meeting new people or dogs, and that’s OK. If your dog doesn’t like it, then please stop introducing him to strangers (i.e. other dogs, children) and accept it’s part of your dog’s personality. If you’re not sure whether or not your dog is friendly, please seek advice from a professional and experienced dog trainer.

What Should You Do Next?

Remember, it’s very important to find the reason for your dog’s sudden aggression because then it can be addressed.

Steer Clear of Triggers

Keep your dog away from whatever caused his sudden burst of aggression until your dog is seen by a veterinarian. Use sturdy baby gates and crates to keep your dog safely confined when guests come over or when children are playing. If your dog is aggressive toward another dog, keep all household dogs separated and stop allowing your dog to visit other dogs.

RELATED: Multiple Dog Household Tips

See Your Veterinarian

Always start with ruling out any and all medical issues. If your dog is in pain, a complete veterinary exam, blood work, X-rays and additional diagnostics should discover the cause of your dog’s pain and sudden aggression.

If pain isn’t causing your dog’s aggression, then ruling out illness is extremely important. Seizures, low or high thyroid levels, anxiety, and chronic illnesses can cause sudden aggression in dogs to happen, so always see a veterinarian first.

Find a Professional Dog Trainer

Once medical issues have been completely ruled out by your veterinarian, it’s time to find a professional dog trainer. If your dog has bitten someone or another dog, you need help from a veterinary behaviorist first and then follow up with a dog trainer. Check out these tips on finding an experienced dog trainer who specializes in dog aggression as well as locating a veterinary behaviorist. These articles will help you narrow your search quickly.

Sometimes, it’s difficult figuring out the exact cause for sudden aggression in dogs, but keep digging and work with a positive reinforcement dog trainer.