Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Why Is My Dog Grumpy All of a Sudden? 7 Vet-Reviewed Possible Reasons

Written by: Ashley Bates

Last Updated on August 28, 2024 by Dogster Team

brown dog stands outside the window

Why Is My Dog Grumpy All of a Sudden? 7 Vet-Reviewed Possible Reasons

Just like us, our dogs change a lot over time, so we can’t expect them to be exactly the same from one day to the next. They have off days, periods of illness, or just the general blues. They are sensitive to their surroundings just like us and can contract illness and disease or become bored.

So, if you have a grumpy puppy or adult dog, what exactly is the cause of your pup’s grumpiness? We’ll discuss several potential causes and how you can pinpoint the problem.

dogster paw divider

The 7 Possible Reasons Why Dogs Act Grumpy All of a Sudden

1. Fear

If your dog suddenly becomes frightened of something, it can cause fear-based reactions that can make them seem off or grumpy. Fear can happen for numerous reasons, but if it’s happening in your home, there’s likely a very direct reason.

Often, dogs don’t respond well to change. So, if they see something new or unfamiliar, it can trigger a not-so-happy response in them. Fear is often pretty easy to detect in dogs as it carries classic body language. A dog that is afraid will likely fold their ears back, tuck their tail between their legs, cower, crouch, and shy away.

Since fear can sometimes lead to aggression, including biting, it is essential to recognize the signs that your pup is fearful and take steps to address the issue as soon as possible.

Scared brown dog under a furniture
Image Credit: Patrick H, Shutterstock

2. Lack of Exercise

If your dog has quite a bit of pent-up energy, they might seem much more ornery than usual. If this energy isn’t being released, they’re going to need to find an outlet for it. That could involve grumpy and destructive behaviors, increased vocalization, and several others.

If your dog seems a little more spicy than usual, it is important to provide appropriate entertainment and outlets, even if you can’t be there to interact directly. Also, make sure that you don’t have an energetic breed locked up in a kennel for long periods.

Often, people buy dogs because of the way that they look or because of something very specific about their particular breed without always fully understanding the activity levels. If you have yet to learn about your dog’s breed, it is important to brush up on the facts. Learning more about their overall temperament can help you navigate these interesting challenges.


3. Hormones

Hormones can play such a huge role in how our dogs interact with us. Just like with humans, if your dog’s hormones are changing or they’re out of whack in any way, it could cause behavioral changes. When a dog is in heat, for example, she might become a little more lovable than usual or change other aspects of her behavior.

The hormonal changes that occur during adolescence often lead to a variety of behavioral changes. Adolescent dogs can become more easily over-aroused or stressed, and excitement and anxiety levels can be higher. They often have more extreme reactions to things that didn’t worry them, and may have changes in their sociability which can make them appear grumpy.

labrador retriever dog lying on the floor looking sad or sick
Image Credit: Jaromir Chalabala, Shutterstock

4. Health

If an underlying health condition causes pain or neurological changes, it could result in behavioral changes. One such change is your dog seeming grumpier than they normally are.

Because issues that can cause the changes are so vast, there’s no way to cover them all in a single article. However, here are some of the issues that could result in mood changes:

  • Sensory loss (blindness, deafness, etc.)
  • Dental disease
  • Canine Cognitive Dysfunction (Dog Dementia)
  • Hypothyroidism
  • Epilepsy
  • Brain tumors
  • Arthritis
  • Infections
  • Inflammation

If you think this is happening due to an underlying health condition, you should make an appointment with your vet right away. Even though it can be something very simple, it is essential to know for sure.

💛 🐶 Speak To a Vet Online From the Comfort of Your Couch!
PangoVet

If you need to speak with a vet but can’t get to one, head over to PangoVet. It’s an online service where you can talk to a vet online and get the personalized advice you need for your pet — all at an affordable price!


5. Environment

Your dog’s environment can certainly change the way that they behave. After all, think about being around people or situations that you already know. You know that certain situations can make you a little bit more on edge or grumpier than others.

If your dog doesn’t like the people or other pets in their environment, they might be on edge. Let’s just say you have family come into town, and they have a particularly rambunctious child that your dog isn’t used to.

The energy shift and increased noise are enough to make a dog seem off-put or grumpier than normal. If these changes are temporary, the situation will resolve itself when they either get used to the person or other animal or when they leave.

small Jack Russell Terrier dog in window
Image Credit: thka, Shutterstock

6. Injury

If your dog has an injury that you haven’t quite picked up on yet, it certainly might be the culprit of grumpiness. After all, when we’re feeling pretty crummy, the last thing we want to do is have other people bombarding, touching, or interacting with us in certain ways.

Our dogs can go out into the yard and get into all sorts of things they shouldn’t have. They also romp around the house and seem to pay basically no mind to whatever is happening around them.

It’s no wonder that our dogs get hurt occasionally. Like any other injury, it might be just a small slight that will pass, or it could require a little bit more attention. It’s hard to say for sure unless you get them evaluated by your veterinarian.

You can do a little self-evaluation at home, gently touching them to check for tenderness. If your dog becomes uncomfortable, fidgets, vocalizes, or shows any other sign of discomfort, you may be able to pin it down to a location before you even get into your appointment. However, if your dog is showing signs that they are unhappy or grumpy about you examining them, it is best to leave it to your vet.


7. Life Changes

Everyone’s a little sensitive to changes sometimes. Our dogs don’t like them either! If you’ve recently moved households, had a new addition or family come to stay, started being away from home more than usual, or any other routine change, it can be very problematic initially for your dog.

Don’t worry, most of these things just take a bit of time to adjust to, but eventually, it all works itself out. Try and make changes gradually where possible, and follow some sort of routine. Making sure your dog has plenty of physical exercise and mental stimulation can also help keep them calm when things change for them.

Welsh Corgi Pembroke in dog park dog owner playing
Image Credit: Hrecheniuk Oleksii, Shutterstock

Dogster_Website dividers_v1_Jan 18 2024-03

Conclusion

Now you understand why dogs might be acting a little more on edge than usual. If you seem like you have an unusually grumpy puppy or adult dog and it seems totally out of character or you can’t find a cause, it’s time to make an appointment with your vet.

Personality changes can be a simple phase or something that requires attention. Leave no stone unturned when it comes to canine health by staying vigilant. It’s always best to be safe rather than sorry.


Featured Image Credit: StrDr stock, Shutterstock

How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

PangoVet Image Speak With A Vet Online

Get Dogster in your inbox!

Stay informed! Get tips and exclusive deals.
Dogster Editors Choice Badge
Shopping Cart

Pangolia

© Pangolia Pte. Ltd. All rights reserved.