Mountain Animal Hospital

Atopy (Environmental Allergies)

Atopy is described as a hypersensitivity reaction to particles in the environment, usually because of a genetic predisposition.  Some examples include pollens, molds, weeds and dust.  Symptoms usually start to appear between 1 and 3 years of age, but can occur at any age.  The most common symptom of environmental allergies is itchy skin (licking, chewing, scratching, and rubbing).  Dogs tent to be itchy around the face, sides of the body, groin, armpits, feet and ears.  In cats, the scratching may be concentrated around the neck, head and ears, or may involve other areas such as the belly, back of the legs or sides of the body.  If we have ruled out other possibilities for itchy skin, and especially if your pet’s skin disease occurs seasonally we often begin treatment for allergic skin disease.  If your pet is allergic to an indoor allergen, however the symptoms may be present year round.  One option at this point is to consult with a veterinary dermatologist (skin specialist) and have your pet allergy tested (more information below). 

Here are some common therapies used to manage environmental allergies:


Many human antihistamines can be used in our pets too!  The benefit of using antihistamines is that they can be used long term without the concern of side effects like other medications (e.g. prednisone).  They can also be used with prednisone to lower the overall amount of prednisone required.  Ask us about which ones are safe and the appropriate dose for your pet.

Shampoo therapy

There are many different shampoos available that may be of help for dogs with environmental allergies.  Cortisone based shampoos can help with itchy skin.  If secondary infections occur because of an underlying allergy then anti-bacterial or anti-yeast shampoos can be used to help treat these infections.



Allerderm spot on

This product is applied directly to your pet’s skin and contains fatty acids and ceramides. These compounds are found in healthy skin and help protect the deeper layers of the skin from allergens in the air.  In dogs and cat with allergies, the normal fatty acid and ceramide barrier becomes thinner or doesn’t work properly, so the Allerderm spot on can help replace them.

 Atopica (Cyclosporin A)

This is an immunosuppressant that is used as an alternative to prednisone.  It can be particularly useful in young patients who we want to avoid having on prednisone for years, or patients who don’t tolerate prednisone well due to its side effects.  It is also a good option for patients who might not be good candidates for prednisone (e.g. diabetics).  Long term use of Atopica does require regular bloodwork monitoring to assess liver and kidney function.


Omega-3-Fatty Acids (EPA and DHA)

These natural oils are found in high amounts in certain fish, like salmon.  They can be helpful in animals with skin disease because they act as anti-inflammatories.

Topical steroids

There are many steroid preparations that are available in creams and sprays that can be used directly to the affected area of skin.  Topical steroids are great if there is only a certain part of your pet’s body that is itchy (for example the feet).  Many topical steroids have very little to no absorption into the bloodstream and are therefore much safer than systemic steroids.

Prednisone and other corticosteroids (e.g dexamethasone, Medrol, prednisolone)

Prednisone is by far the most widely used medication for managing environmental allergies, probably because it works so well as an anti-inflammatory for itch relief.  Unfortunately, long term prednisone use can result in side effects including gastrointestinal irritation, liver disease, thinning of the skin, urinary tract infections and symptoms of Cushing’s disease.  Many dogs and cats with allergies do require some prednisone during the year to keep them comfortable, but our goal is to keep this to a minimum, by using the other treatment options listed above.  It is preferable to use a small amount of prednisone periodically to “put out the fire” rather than continuous, long term use.  Regular bloodwork checks while your pet is taking prednisone ensures that it is still safe to use this medication.

Allergy injections (Immunotherapy)

As mentioned above, allergy injections can be formulated by a dermatologist (skin specialist).  The benefit of allergy testing is that there is a possibility your pet may require no other treatment other than allergy injections!  The more common scenario, however is that your pet may still need to be on some medication but to a much lesser degree.  We are happy to set up a referral to a veterinary dermatologist if you are interested!