Why Your Dog Won’t Stop Scratching, And It Might Be Mites

Your dog has been scratching again. And again. You've checked for fleas, you've changed their shampoo, you've tried everything you can think of, but the itching just won't stop.

Before you chalk it up to dry skin or seasonal allergies, there's another possibility worth considering: mites. Tiny and surprisingly common, mites are one of the most frequently overlooked causes of persistent skin problems in pets.

Here's how to recognise the signs, understand what you're dealing with, and know when it's time to act.

What Are Mites?

Mites are microscopic parasitic arachnids that live on or within your dog's skin. Unlike fleas, which you can sometimes spot moving through your dog's coat, mites are virtually invisible without a microscope, which is part of what makes them so difficult to detect without veterinary help¹.
 

There are several types of mites that commonly affect dogs, and each causes distinct clinical signs:

• Sarcoptic mange, also known as scabies. This is one of the most intensely itchy conditions a dog can experience. Sarcoptic mites burrow into the skin to lay their eggs, triggering a severe allergic response and can cause extreme discomfort².

• Demodectic mange naturally live in small numbers in a dog's hair follicles and are usually harmless. Problems arise when the immune system is compromised in puppies, elderly dogs or those under significant stress, causing mite populations to multiply uncontrollably².

• Ear mites live in the ear canal and are highly contagious between animals. They often infect the external ear and cause intense irritation, leading to frantic head shaking, ear scratching, and a dark discharge from the ear². 

Among these, ear mites are the most commonly encountered cause of ear infections in dogs, accounting for up to 50% of infection of the outer ear canal (also known as otitis externa cases), and can easily go unnoticed, making protection against ear mites extremely important.

In addition, research shows that up to 25–30% of dogs may experience skin-related issues at some point in their lives, with parasites like mites being a key contributing factor¹⁰.

Signs Your Dog Might Have Mites

Because mites are invisible, recognising an infestation means paying close attention to your dog's behaviour and skin condition. Watch for the following^2,4:

• Intense, persistent scratching, particularly if it seems disproportionate to any visible cause, or if it worsens at night. Severe itching may also cause secondary symptoms in dogs, including weight loss, depression, decreased appetite, lethargy and enlarged lymph nodes. ^.

• Hair loss (alopecia) that is often patchy and localised, appearing first around the ears, elbows, face, and legs, or around the eyes and muzzle.

• Thickened, crusty, or scaly skin, where the skin may appear red, inflamed, or develop a rough texture in affected areas.

• Head shaking or pawing at the ears, often accompanied by discharge and an unpleasant odour.

• Restlessness or difficulty sleeping.
• Skin infections due to the repeated scratching that breaks the skin barrier.

Your vet will likely perform a skin scraping, a simple procedure where a small sample of skin cells is collected and examined under a microscope to identify the presence of mites or their eggs⁸.

Depending on the type of mite and the severity of the infestation, treatment may include topical lotions, medicated shampoos, or oral antiparasitic medications such as NexGard SPECTRA®, which treats and protects against external parasites including certain mite species, such as demodex, scabies and ear mites. In cases where secondary bacterial infections have developed, antibiotics may also be prescribed. It may also be necessary to clip the dog’s hair.

Persistent itching in dogs deserves more than a wait-and-see approach. If the scratching isn't resolving, or is getting worse, mites are a real possibility that warrants a proper diagnosis. Besides mites, persistent scratching could also be driven by other factors including^5,6,7:

• Flea allergy dermatitis, which is an allergic reaction to flea saliva, even from a small number of fleas.

• Environmental or food allergies, such as pollen, dust mites and certain proteins.

• Bacterial or fungal skin infections.

• Contact dermatitis, due to a reaction to grooming products, household cleaners, or certain plants.

Not Sure What's Causing Your Dog's Itch? Start With Parassess®

If you're uncertain whether mites, fleas, ticks, or another parasite could be behind your dog's symptoms, Parassess® is a useful starting point⁶. This free online tool assesses your pet’s lifestyle and environment to estimate parasite risk, then generates a personalised report to support discussions with your veterinarian, helping guide appropriate parasite prevention choices. 

Based on your dog’s needs, your vet may recommend options such as NexGard SPECTRA®, which not only offers the most complete protection against external and internal parasites, but is also proven safe for puppies, adult dogs, and breeding, pregnant or lactating females. 

NexGard® products are available only with a veterinary prescription.

1. https://nexgard.com.au/dog-parasites/mites/mites-on-dogs 

2. https://www.msdvetmanual.com/dog-owners/skin-disorders-of-dogs/mite-infestation-mange-acariasis-scabies-in-dogs#Trombiculosis_v3207348 

3. https://www.petmd.com/dog/conditions/skin/mange-dogs 

4. https://www.petmd.com/dog/symptoms/itchy-dog 

5. https://www.msdvetmanual.com/dog-owners/skin-disorders-of-dogs/itching-pruritus-in-dogs 

6. https://www.boehringer-ingelheim.com/animal-health/animals-we-support/dogs/risk-parasites-dogs 

7. https://nexgard.my/en/products/nexgard-spectra 

8. https://www.dialavet.com/vet-answers/demodex-mites-return-after-treatment-388944 

9. https://wsava.org/global-guidelines/dermatology/ 

10. https://www.akc.org/expert-advice/health/ear-mites-in-dogs/