Are You or Your Pet Itching to Learn About Allergy Medications?
While treating infection and working up the underlying allergic cause for infections/itch, we often need to help your pet feel more comfortable at the same time. The over-the-counter products (ex. topicals, antihistamines, vitamin E, fish oils, etc.) may be relatively safe, but this often means that they don’t provide as much comfort as needed for a severely itchy pet. Therefore, your veterinarian and/or veterinary dermatologist may prescribe a medication. One drug may be recommended over another for an individual based on concurrent medications/diseases, previous response, level of itch, underlying cause, future diagnostics, and risk vs. benefit. In particular, if the cause for itch is not allergic, then these medications may not apply. Some level of labwork monitoring may be required for use of these medications.
Steroids (ex. Prednisone, Prednisolone)
PRO
- Long-term experience (“tried and true”) in both humans and animals
- Works very quickly for itch (<24 hours)
- Most helpful for ears and for inflammation
- Can use in most ages of dogs AND cats
- Comparatively inexpensive
- Can script out oral to human pharmacies for dogs (cats require prednisolone)
- Injectable forms available, although usually not preferred for long-term treatment
CON
- Short-term side effects: increased thirst/urination/hunger/panting (dogs); and behavioral changes
- Long-term side effects: “when” not “if,” gastrointestinal (stomach ulcers), liver (steroid hepatopathy), joints (predispose to cruciate tears), diabetes mellitus (especially cats), calcinosis cutis, immunosuppression (urinary tract infections, pneumonia), etc.
- Needs to be tapered gradually, especially with long-term use
- Can’t skin test while on this medication
- Can’t use concurrently with non-steroidal anti-inflammatory drugs (NSAIDs = ex. Rimadyl, Deramaxx)
- Can potentially mask other non-allergic disease processes (ex. immune-mediated, cutaneous lymphoma)
- Tachyphylaxis: repeated courses may be less and less effective over time
Apoquel® (oclacitinib) – JAK/STAT inhibitor FDA approved 2013 for symptomatic treatment of allergic itch in dogs > 1-year-old
PRO
- Works very quickly for itch (<24 hours)
- Moderate expense: cost is based on number of tablets rather than size of tablet
- Fewer short-term side effects: mild gastrointestinal most common
- Can skin test while on this medication
- Can likely be used concurrently with more medications
CON
- Not labeled for cats OR for dogs < 1-year-old
- Not labeled for patients with a history of cancer
- Limited long-term experience/data: mildly elevated liver enzymes, low normal white blood cell count, immunosuppression
- Can’t decrease frequency of medication: typically stays at daily oral tablet for maintenance
- Rebound effect: does not require tapering strictly like steroids, but ideally weaned off gradually
Atopica® (modified cyclosporine) – calcineurin inhibitor FDA approved 2003 for atopic dermatitis (environmental allergy) in dogs AND cats > 1-year-old
PRO
- Can skin test while on this medication
- Can help for itch in dogs AND cats
- More experience/data in both humans and animals compared to Apoquel®
- Many other dermatologic and medical uses (ex. perianal fistulas, pemphigus foliaceus)
- Can potentially be tapered (ex. every-other-day, 1-2x/week)
CON
- Short-term side effects: gastrointestinal (most common)
- Long-term side effects: immunosuppression (urinary tract infection, pneumonia) and recurrence of viral infections, liver/kidney (rare, more common in humans),excessive hair growth, gum tissue overgrowth
- Must be cautious for cats that have not previously been exposed to Toxoplasma: indoors, no raw food, no hunting, no new cats
- Can’t use concurrently with some drugs
- High expense: recommend starting with brand name before considering possible generic
- Compounded formulation not recommended, only comes in oral capsules or liquid
- Not labeled for pets < 1-year-old
- Not labeled for patients with a history of cancer
- May take 4-6 weeks for maximal effect
CytopointTM (formerly known as canine atopic dermatitis immunotherapeutic = CADI) (lokivetmab) – IL-31 monoclonal antibody USDA approved 12/2016 for allergic itch in dogs
PRO
- Mechanism of action is supposed to be most specific and therefore have fewer side effects
- Few and mild short-term side effects: gastrointestinal, lethargy, skin infection (unclear if related to injection vs. allergy)
- Monthly subcutaneous injection by veterinarian, no pills at home
CON
- Limited experience, was on conditional license since 2015 for most dermatologists
- Long-term studies not available currently
- Supposed to last 4-8 weeks but clinically may be shorter duration
All of these drugs are only treating the symptom of itch. Underneath this “band-aid,” there is still an underlying problem that needs to be addressed, whether with flea prevention for flea allergy vs. a food trial for food allergy vs. immunotherapy based on skin testing for environmental allergy. Relying solely on these medications can be problematic, particularly for a young patient if other systemic diseases develop over time that preclude their use. Please consult with your veterinarian further for specific questions about your own pet.
Friendship Dermatology Specialists, led by Dr. Darcie Kunder and Dr. Fiona Lee, is the only board-certified veterinary dermatology group in the District. Specially trained to treat a wide variety of conditions affecting the skin, hair and nails, Friendship Dermatology Specialists see appointments Monday through Friday.
*Featured image courtesy of Animal Skin and Allergy Clinic.
