Dust Mites Allergies in Dogs

Your dog gets allergies just like you do, from different foods (corn, grain, fish, chicken, beef), pollen, dander, and fleas. A dust mite allergy is caused by tiny spider-like creatures that live in our homes to eat the dander (skin and hair flakes) from our bodies. They are not visible to the naked eye, but under a microscope they look similar to a white flea, but they are actually related to the spider and have eight legs. Mites (and their waste) get onto the skin and breathed in by the lungs whether the mites are dead or alive, so just killing them is not the answer. You have to rid the entire house of the bodies and the waste they produce to make your home truly dust mite free, but it is next to impossible to do such a thing. The symptoms are red and oozing skin, rash, licking excessively, scratching, and redness and watering of the eyes and nose. If your dog has a severe reaction, it may also produce inflammation of the airway (anaphylaxis) and cause a constriction that makes it hard to breathe. Because of this, if you notice your dog sneezing, coughing, and wheezing you need to go to an animal hospital right away.

Dogs with dust mite allergies can be misdiagnosed because the symptoms are very similar to other conditions. The scratching and inflammation may be mistaken for fleas, dry skin, or chronic dermatitis when it is actually the dust mite causing the reaction. Dust mites are microscopic organisms that live in every home no matter how much you clean. In fact, it is during or after vacuuming or dusting that the allergy seems to get much worse. The main difference between dust mite allergy and other causes of itchy skin (dermatitis, dry skin, fleas) is that with dust mite allergy your dog will also have sneezing, runny eyes and nose, a cough, and possible wheezing. Though not typically documented as a problem with dust mites allergies, studies show that anaphylaxis, a life-threatening emergency causing swelling of the airway and inability to breathe, is possible. Any time that your dog is having breathing abnormalities or is in distress due to itching and scratching, a veterinary visit is needed without delay.

Symptoms of dust mite allergy may be varied:

• Bald spots from scratching
• Excessive licking
• Hives
• Moist or crusty skin
• Red and watery eyes
• Runny nose
• Scratching over the body include tail area, eyes, and underarms
• Sneezing
• Snoring caused by an inflamed throat

 Types

All dogs of any breed, gender, and age can develop an allergy to dust mites, but it is more frequently seen in:

• Dogs over three months old
• Bulldogs
• German Shepherds
• Miniature Schnauzer
• Pugs
• Retrievers
• Setters
• Terriers

Dust mite allergies in dogs are caused by dust mites, their dead bodies and body parts, and dust mite waste. If your dog has been having symptoms the entire year and seems to breathe better outdoors, you might suspect dust mite allergies. There are several ways your dog can be exposed to dust mites:

• Body parts
• Dust mite bodies (dead)
• Dust mites (alive)
• Waste from dust mites

Diagnosing your dog may be hard to do because it seems to be just a general, all over itchiness and runny nose and the veterinarian may think it is just dry skin or chronic dermatitis. You should mention if your dog is fine while outside and that it is a year-round condition. The veterinarian will do a complete and thorough physical exam including skin and coat condition, general health, vital signs, as well as some laboratory tests. Some of the tests your veterinarian may suggest are a complete blood count, blood chemistry profile, electrolyte level, bacterial and fungal swab, urinalysis, and fecal examination.

Even with a physical examination, the veterinarian may not suspect an allergy to dust mites because skin afflictions are so common. However, if your dog is fine while outside but itchy indoors and if it gets worse during or after vacuuming or dusting, you should call your veterinarian and have your dog tested for dust mite allergy.  

Serum Allergy Test

If you think dust mites are the cause of your dog’s itchiness, be sure to mention this to your veterinarian and ask for a serum allergy test. This test is done by using a blood sample that is tested for signs of allergic response. 

Intradermal Allergy Testing

This test is done by the dermatologist and costs a little more than other tests, but it is considered to be the most accurate test for topical allergens. In this procedure, your dog will be sedated and they will shave an area to be tested (usually on the side). The dermatologist will use a small needle to inject your dog with different allergens (usually about 50-75 of them) and wait to see if they show signs of inflammation or redness. 

Some possible treatments for allergies in dogs are corticosteroids, antihistamines, and topical ointments, such as a cortisone cream or gel. Additionally, a special shampoo may be prescribed to decrease the itching and an antibiotic to prevent infection.  There are other medications that might be prescribed, as well.  

Immunotherapy Injections

These injections are just like allergy shots for humans, and they tend to be effective, but can take a long time to work. The veterinarian will show you how to give your dog an injection with a small amount of allergen daily, adding a bit more each day to desensitize your dog to dust mites gradually. The problem with this method is that it can sometimes take many months of injections before your dog is fully desensitized. In fact, in some cases, it may never work. Also, these injections can trigger a serious reaction called anaphylaxis, which is a life-threatening emergency. Your veterinarian may provide you with an epinephrine pen (epi-pen) to inject your dog with epinephrine in case this complication happens.

Treating the Skin

Your dog’s skin is the best way to determine allergies, so it is important to get the skin back to normal as soon as possible. 

First of all, you have to rid your home of as many dust mites as you can. It is virtually impossible to get rid of them all, but you can make a significant difference by getting rid of carpeting and replacing upholstered furniture with vinyl, leather, plastic, or wood. Use pillow and mattress covers on your dog’s bed as well as your own. You will need to wash all bedding in hot water weekly, or get them professionally cleaned if possible. Studies have shown that professional cleaning gets rid of up to 60% more dust mite allergens than home laundering. Another thing you can do is to use blinds or shades instead of curtains or drapes. Anything that can collect dust (stuffed animals, knickknacks, books) should be removed if you are not prepared to clean them thoroughly every day The carpet is the main culprit of dust mite allergens, but if you cannot get rid of the carpeting, you should steam clean weekly and thoroughly vacuum daily. Be sure to use a HEPA filter on your vacuum cleaner.

Usually, your dog will show improvement with treatment within a few days to weeks, but it can take up to a year or more in some dogs. Immunotherapy or skin creams do not cure the allergies, but these treatments do make your dog more comfortable and can prevent a secondary infection from scratching. No matter which treatment works for your dog, you have to stick to the regimen for the rest of your dog’s life in order for it to work. If you stop the treatment, the symptoms will come back and they may be worse than before. If you have questions or concerns, give your veterinarian a call right away.