Ear Mites in Dogs: Mites, Symptoms, and Treatment
Ear Mites in Dogs: Mites, Symptoms, and Treatment
What is ear mites in dogs?
Ear mites is an ear canal condition in dogs caused by the mite Otodectes cynotis. The mites live on the surface of the ear canal and the outer ear, feeding on tissue fluid and earwax, and causing severe inflammation and intense itching. Ear mites are the most common parasitic cause of otitis externa in dogs—and are particularly prevalent in puppies and young dogs.
Otodectes cynotis is highly contagious between dogs and cats—infected cats in the same household are often the source of the infection. Effective treatment must include all animals that have been in contact with the infected animal.
Background + Scientific Context
Merchant (1994, Veterinary Clinics of North America, PubMed 7992776) describes ear mites in the context of cutaneous parasitoses: Otodectes cynotis is an obligate ectoparasite—it cannot permanently leave the host but can survive briefly in the environment (up to 10–12 days outside the host). The zoonotic risk to humans is low but has been described: papular skin lesions in humans following close contact with animals have been documented. Treatment of all contact animals in the household is mandatory.
Wall and Shearer (2001, *Veterinary Ectoparasites*) describe the life cycle of *Otodectes*: The complete cycle from egg to adult mite takes 3 weeks. Mites reproduce rapidly; untreated infections lead to massive colonization of the ear canal, secondary bacterial and yeast infections, and potential damage to the eardrum. Early diagnosis and consistent treatment prevent chronic complications.
Blot et al. (2003, Veterinary Record, PubMed 12703640) investigated the efficacy of selamectin (Revolution) in treating parasitic otitis: Selamectin (spot-on) demonstrated highly effective kill rates for Otodectes after a single or double application—easier to use than direct ear drop treatments and well tolerated. Modern broad-spectrum antiparasitic agents (selamectin, moxidectin, ivermectin) are the therapeutic standards.
Vitomalia-Position
Ear mites are a classic example of a condition where self-diagnosis can lead to incorrect treatment—because excessive head shaking and scratching can also be signs of many other ear conditions. Any dog exhibiting these symptoms should undergo an otoscopic examination: A diagnosis of ear mites is relatively easy to make through direct detection of the mites and an otoscopic examination.
When does ear mites become a concern?
- Puppies and young dogs: high risk of exposure, especially when in contact with cats
- Adopting a dog from a shelter or breeder
- Simultaneous ear problems in multiple animals in the household
- Intense scratching, head shaking, dark, crumbly ear discharge
- Treatment must include all animals that have been in contact with the infected animal (including cats that show no symptoms)
Practical application
Clinical signs:
| Character | Description |
|---|---|
| Intense scratching | Frequent bloody scrapes behind the ears |
| shaking one's head | Frequent, often persistent |
| Dark ear discharge | Resembling coffee grounds, dry and crumbly |
| Redness of the outer ear | Signs of inflammation |
| Otoscopically | Mites visible (white, moving dots) |
Diagnosis: - Otoscopy: Mites are directly visible (small, white, moving organisms) - Ear swab examined under a microscope: mites, eggs, and feces detected - Differential diagnosis: bacterial/yeast otitis, foreign body — can be distinguished by otoscopy
Treatment: - Spot-on treatments effective against Otodectes: selamectin, moxidectin (Revolution, Advocate) - Ear drops: Ear drops containing ivermectin, administered twice at 3-week intervals - Treat all animals that have been in contact with the infected cat—including asymptomatic cats in the household - Cleaning the living area: cleaning/washing sleeping areas and blankets - In cases of secondary infection (bacteria, yeast): combined antibiotic/antifungal therapy
Common Mistakes & Myths
- “Only one ear is affected—so it’s not ear mites.” Otodectes infestations may start on one side, but usually spread to both ears. A one-sided infestation does not rule out ear mites.
- "If I treat my dog, the rest of the household is safe." Cats are often asymptomatic carriers of Otodectes. Without treating the cat at the same time, the dog will become reinfected.
- “The discharge looks like dirt—I’m just cleaning the ears.” Dark, crumbly ear discharge (resembling coffee grounds) is a characteristic sign of ear mites. Cleaning alone does not remove the mites—consistent antiparasitic treatment is necessary.
Current State of Research (2026)
Otodectes cynotis remains the most common parasitic cause of otitis externa in dogs. Modern spot-on treatments (selamectin, moxidectin) are well tolerated and reliably effective. No cases of resistance have been reported in ear mites to date. The risk of zoonosis is low but real: veterinarians recommend taking hygienic precautions during close contact with infected animals.
Frequently Asked Questions
How can I tell if my dog has ear mites?
Typical signs: intense scratching of the ears (often leading to abrasions), frequent head shaking, dark, coffee-ground-like discharge in both ears, redness of the outer ear. Diagnosis is made through an otoscopic examination by a veterinarian—mites are visible under the otoscope as white, moving dots.
How is ear mites treated in dogs?
Treatment with spot-on medications (selamectin, moxidectin) or ear drops containing antiparasitic agents. All animals in the household that have come into contact with the affected animal (including cats without symptoms) must be treated at the same time. Wash sleeping areas and bedding. In case of a secondary infection: additional antibiotic/antifungal ear treatment.
Can I catch ear mites from my dog?
The risk is low, but has been documented: Otodectes cynotis can cause temporary papular skin lesions in humans, but does not establish a permanent infestation in humans. Hygiene precautions should be taken when handling infected animals.
Related terms
Sources & Further Reading
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Merchant, S. R. (1994). Zoonotic diseases with cutaneous manifestations: Part I. Parasitic zoonoses. Veterinary Clinics of North America: Small Animal Practice, 24(5), 827–843. https://pubmed.ncbi.nlm.nih.gov/7992776/
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Wall, R., & Shearer, D. (2001). Veterinary Ectoparasites: Biology, Pathology and Control (2nd ed.). Blackwell Science. ISBN 9780632056101.
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Blot, C., Kodjo, A., Reynaud, M., & Bourdoiseau, G. (2003). Efficacy of selamectin administered topically in the treatment of feline otoacariosis. Veterinary Parasitology, 112(3), 241–247. https://pubmed.ncbi.nlm.nih.gov/12703640/