Get

In Your Inbox

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 Itching All of a Sudden? 5 Vet-Reviewed Causes

brown dog is scratching

Just like humans, it’s normal for dogs to scratch themselves every now and then, but when they start doing it frequently, it’s a little more concerning.

Though the common skin conditions behind itchiness in dogs are uncomfortable, the good news is that many are easy to treat as long as you consult your vet to determine the appropriate medication and/or management techniques. Let’s look into the most common causes of sudden itching in dogs.

dogster face divider

The 5 Causes of Sudden Itchiness In Dogs

1. Fleas

If there’s one word sure to get dog parents everywhere sweating, it’s “fleas”. Dogs get fleas by being in contact with other dogs with fleas or contact with materials that fleas have gotten onto, like coats, socks, and bedding. They can also contract a flea infestation from grass (outdoor animals like mice and foxes can deposit fleas here) or by visiting new places.

Fleas not only live on dogs and make them itchy in general, but some unlucky dogs suffer from flea allergies, which makes the itching more severe.

Signs of an infestation include scratching, visible flea dirt, bite marks, a rash, turning to bite the rear end, infected skin, wounds, and patchy hair loss. Speak to your vet about year-round flea preventatives—dogs can catch fleas at any time of year, not just when it’s warm—and how best to treat an existing infestation.

close up fleas on cat
Image Credit: KanphotoSS, Shutterstock

2. Other Parasites

In addition to fleas, other parasites like mites can cause signs like itchiness, redness, skin sores, scabbiness, and bald patches. Mange (skin disease caused by microscopic mites) can affect various areas of the body, including the face, inside the ears, armpits, belly, and legs. The condition can also cause some dogs to smell if their skin gets a secondary bacterial or yeast infection.

There are two common types of canine mange: sarcoptic (can be passed to humans) and demodectic (cannot be passed to humans). Treatment options are prescribed by a veterinarian and can vary depending on the specific type of parasite. Other pets at home may also need to be treated.


3. Skin Infections

Bacterial and yeast skin infections are other common causes of itchiness. They are often secondary to another underlying condition such as allergy or hypothyroidism. You may also notice odor, redness, hair loss and flakiness. Staphylococcus (staph) infections are the most commonly seen bacterial skin infections, while Malassezia is the most common cause of yeast dermatitis. Ringworm, is another fungal infection that can cause patches of hair loss, inflammation, scaliness and can be itchy.

The treatment of a skin infection depends on the type, location, how badly the dog is affected, and any concurrent conditions. Topical products such as medicated shampoos are used if possible. Underlying conditions need to be investigated and addressed.

dog itching
Photo Credit: photo-vista.de/Getty Images

4. Allergies

If your dog’s immune system overreacts to something, it means the dog has an allergy. The term “allergies” is a broad umbrella and includes:

  • Environmental allergies: These include things like dust mites, pollen, and mold spores.
  • Food allergies: Common food allergens are proteins including chicken, beef, and dairy.
  • Insect bites and stings: Some dogs are allergic to the bites and stings of insects like fleas, mosquitoes, horseflies, bees, and wasps, and arachnids like spiders and ticks.
  • Contact allergies: These are caused by substances like plants, shampoos, cleaning products, and insecticides.

Allergic reactions can produce a number of symptoms, and itchiness is just one of them. Treatment options vary greatly because there are so many different kinds of allergies, but they include anti-inflammatories, shampoos, and prescription diets.


5. Underlying Health Conditions

Sometimes, the causes of itchy skin are not so obvious, as is the case with underlying health conditions and nutritional imbalances. Poor diet and hormonal conditions like hypothyroidism or Cushing’s can manifest in the form of skin issues.

Skin infections, dryness, dandruff, patchiness, sores, scaliness, poor coat condition, and excessive shedding are all possible signs of underlying health conditions and/or poor nutrition, so please consult with your vet if you spot any of these.

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!

PangoVet_Mention-in-Content Savings V1

How Do I Get My Dog to Stop Scratching?

There’s no straightforward answer to this question because there are so many potential causes that could be behind itchy skin in dogs, which means there could be a number of possible treatments. Some conditions need specific medications whereas for others, management techniques like nutritional changes are required.

The best way to get to the bottom of things and get your dog on the right course of treatment is to have them checked by a vet. Please refrain from treating your dog yourself with human medications like antihistamines without the go-ahead from a vet.

dogster face divider

Conclusion

Itchiness is sometimes overlooked by dog parents as “normal”, but it’s essential to seek veterinary advice because untreated skin conditions can make life pretty miserable for dogs.

To recap, some of the signs that your dog should be checked out include frequent scratching, chewing, licking or biting at the skin, rolling or rubbing against things regularly to gain relief, patchiness, dryness, excessive shedding, flakiness, a musty smell, redness, inflammation, sores, and skin thickness and color changes.

Also See:


Featured Image Credit: GettyImages

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

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?

Join the conversation

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.

Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

Crates Are Great: 7 Reasons Dr. Karyn Loves Them

Hi, I’m Dr. Karyn. Read my introduction to learn more about me and my five funny dogs, Poppy, Bailey, Kodah, Ned, and Fred....

How Much Does It Cost to Cremate a Dog? 2025 Price Guide

Being the pet parent to a lovable dog is one of life’s great joys. Like all living creatures, however, the day will inevitably...

Vacation on a Dog-Friendly Cruise This Summer

In Shall We Dance, the 1937 musical comedy film featuring Fred Astaire and Ginger Rogers, partially set on an ocean liner, numerous dogs...

Why Do Dogs Walk in Circles Before Lying Down? 3 Reasons for This Behavior

Have you noticed that your dog almost always circles an area before they decide to lie down? If so, you’re far from alone...

More related

10 Best Dog Foods for Dachshunds in 2025 – Reviews & Top Picks

With their short legs and long backs, Dachshunds are among the most recognizable breeds in the world. Their sausage shape gives them the...

150+ Funny Dog Names: Hilarious Ideas for Dogs, Puppies, & Pets

Are you looking for the perfect funny (or punny) dog name for your new pet? You’ve come to the right place. In this...

10 Best Dog Foods for Bichon Frises in 2025 – Reviews & Top Picks

There are a few things to consider when looking at reviews for the best dog food for Bichon Frises. Keep in mind that...

4 Akita Inu Colors & Coat Patterns (With Pictures)

The Akita Inu, or Japanese Akita, is a large, noble dog with roots in Japan, where they are revered as a national treasure....

Keep reading

Can a Puppy Eat Adult Dog Food? Vet Approved Facts & FAQ

Bringing a new puppy home is an exciting experience. Plenty of responsibilities are involved, like ensuring your new pup gets the proper nutrition for a long, happy, and healthy life. But what exactly should you be feeding your puppy? Is...

Can a Puppy Eat Adult Dog Food

Can Dogs Eat Celery? Vet-Approved Feeding Facts & FAQ

Looking for a healthy snack option for your dog? While you might be tempted to toss them whatever food you’re holding at the moment, there are some foods that are better than others, and celery is a great option, although...

Can Dogs Eat Celery

Can Dogs Eat Frosted Flakes? Vet-Verified Facts & Nutrition Guide

While Frosted Flakes are a popular breakfast food for both children and adults, they’re not so great for dogs. Frosted Flakes don’t add any nutritional value to a dog’s diet, and the added sugar can lead to health complications if...

Can Dogs Eat Frosted Flakes

Can Dogs Eat Thanksgiving Turkey? Vet-Verified Nutrition Guide

As dog owners, we all know how hard it is to say no to pleading puppy dog eyes at the dinner table. But what if your pup is begging for your Thanksgiving turkey? Turkey is a healthy protein so it...

Can Dogs Eat Thanksgiving Turkey

Can Dogs Eat Honeydew Melon? Vet-Verified Nutrition Facts & FAQ

Honeydew melon is a favorite treat to eat in the summer heat. But if your dog is trying to get a piece, you want to make sure it is safe. Can dogs eat honeydew? Yes, dogs can eat honeydew in...

Can Dogs Eat Honeydew Melon

Can Dogs Eat Crickets? Vet-Verified Facts & FAQ

Crickets are insects that belong to the Grylloidea family.1 They typically have long bodies, segmented legs, and large antennae. A tough exoskeleton covers their bodies and provides protection from predators. They can be found almost everywhere in the world except...

Can Dogs Eat_Crickets

Crave Dog Food Review 2025: Recalls, Pros & Cons

Review Summary Crave dog food is a newer brand that offers dry and wet food formulas. The brand promotes grain-free diets and features meat-based lean proteins. Like all AAFCO-approved brands, Crave offers complete and balanced nutrition for dogs. As with...

Dogster_Crave Dog Food Review

6 Eating Problems That Can Affect Dogs: Signs & Treatment

You’re probably familiar with the most common eating disorders in humans, such as anorexia and bulimia. You might not know that dogs can also have eating disorders, but they do not have the same complex mental concerns that plague these...

dog not eating its food