Westcoast Veterinary Hospital/Naples Safari Animal Hospital & Pet Resort

Treating the itchy pet
1.  Ectoparasites – All itchy pets should be treated for fleas whether or not fleas are seen.  
Topical monthly products like Frontline, Advantage or Canine Advantix are effective in reducing
flea populations. A new monthly oral product called Comfortis has also proved to be very
effective.  We will discuss which protocol is best for your pet. In order to get an infestation under
control, product combinations plus continued environmental control will be needed.   If scabies
mites are suspected, we will treat them empirically. If ectoparasites are the sole source of pruritis ,
appropriate treatment will eliminate itching.

2.  Allergies it is important to remember that , as in human medicine, allergies are not cured,
only managed, and most often require lifelong, owner intensive treatment. Allergy treatments
involve 2 major modalities; 1. avoidance & 2. modulation of the immune system.  

Avoidance involves minimizing exposure to the offending irritant.  While this sounds easy it
usually isn’t.  One must first identify what the pet is reacting to.  Often,  the allergen(s) is
something  that  the animal cannot avoid like grass or even pet and people  dander.  There are
some ways owners can help minimize exposure .   If your pet chews his feet after walking on the
grass, make a point of rinsing the feet off after a walk.  Avoid outside exposure at dusk and
dawn,  or after lawn mowing when pollen counts are high.  Cats can be kept indoors to reduce
exposure to pollens.  Once or twice weekly bathing with  a recommended shampoo can help by
removing  offending allergens from the coat to prevent reexposure and absorption,  as well as
being soothing. Many shampoos have medications or additives to help control itch.    If mold or
dust mites are suspected,  a dehumidifier to reduce populations may help.  Do not allow animals
to sleep in the human bed as this is where the highest concentration of dust mites is found.    
Provide separate clean cotton bedding that can be washed weekly.

Modulation of the immune system can be the most effective way of treating allergies.  This can be
accomplished in a number of ways.

1.  Drugs:  Steroids are powerful immune suppressants and are effective at reducing itch
immediately.  They play an important role in treating allergies but can have serious, life
threatening side effects with prolonged use or or at high doses.  The use of steroids is usually
reserved for severe itching or combined with antihistamines for limited periods of time until other
methods can be used.  Antihistamines are more important in treating human allergies than in
pets, only about 20% of dogs will respond to any single antihistamine,  although they seem to be
more effective in cats than in dogs. It is recommended that a 2 week trial of various
antihistamines such as  clemastine fumerate, chlorphinaramine, or diphenhydramine   be initiated
to determine which works best for your pet.  These are extremely  safe, relatively inexpensive
drugs  with very few side effects. Fatty acid supplements are different than the oils usually added
to make a pet’s coat healthy.  They work by being incorporated into the skin where they alter the
production of inflammatory chemicals.  They  take about 4 weeks to be maximally effective.  It is
thought that they may help  antihistamines work better.   Cyclosporine is a drug that can   be as
effective as steroids for reducing itch. It also suppresses the immune system but has fewer side
effects than steroids.  The drawbacks with cyclosporine are that it can take 2-3 weeks to become
effective and can be expensive, especially for larger dogs. Cyclosporine  is often used with oral
antifungal mediations which can help reduce the dosage and treat yeast infections as well.   This
is the often the best option for dogs with severe,  chronic allergies.

2.  Hypo sensitization – just like people, pets can get allergy shots.   Your pets will have to be
tested to determine what allergens they are sensitive to.  The most accurate test is done by
injecting allergens into the skin and noting the reaction.  This procedure must be done through  
referral to a specialist. Testing on blood is simpler and can be done in this office, but may be less
accurate.  Neither method can test for all allergens, only the most common offenders in our area.  
Based on test results,  a serum is formulated especially for your pet.  Injections must be given on
a regular basis by the owner.  75% of dogs will benefit from  hypo sensitization, 25% will not. The
earlier after onset of symptoms that treatment is started, the more favorable the outcome.   It will
take 6-12 months to see a response during which time alternate therapies may be required.

There are no accurate tests available to determine if and to what food  a pet is sensitive to.  The
irritant can be any ingredient or combination of ingredients that the animal has had previous
exposure to, although the most common culprits are beef, chicken, corn, pork, wheat or soy.  
These ingredients can be found in some form in almost every commercial diet.  In order to
determine if a food allergy exists,  the pet must be put on a diet restricted to very few ingredients
to which they have never been exposed to before exclusively for 10 weeks. The ultimate diet
would be homemade to rule out preservatives or additives as well but this is usually not practical
for most owners.  Fortunately, there are a number of commercial diets available specifically for
this purpose.  Please note that diets labeled lamb and rice or sensitive skin etc are not suitable
for this trial as they are not limited ingredient diets! The protocol requires the  involvement  of
everyone that comes in contact with the pet as nothing can pass by the lips except the diet and
water for 10 weeks.  Prohibited items  include treats, rawhide bones, heartworm chews, flavored
toothpaste and (yuk) “litterbox treats” . Diet changes can be especially challenging in felines and
must be done gradually. Often multiple diets may be tried.  Once improvement is noted, the pet
can be challenged by adding various ingredients to the diet for 2 weeks at a time to see if a
relapse occurs. Avoidance is the only effective treatment for food allergies. While this may seem
like a difficult protocol, it must be said that animals with this condition will often show marked
improvements if the owners are willing to be strict.  In animals with multiple sensitivities an
elimination diet  may reduce the “itch threshold” to acceptable levels.

3.  Secondary infections may be treated with topical medications, systemic (oral) medications
or a combination of the two.  Until or unless the predisposing cause is identified and addressed,
multiple rounds of treatment will probably be required.

Please keep in mind that realistically we will probably not stop the itch forever, but with proper
attention, can substantially improve the quality of life for you and your pet.

Lesli R. Reiff, DVM