Does My Dog Have Hay Fever?
- by Scott Smith, DVM
Although our Beagles are a hardy breed, they are also at greater risk than
other breeds for certain types of allergies by way of more frequent exposure to
pollens, plants, insects and other sources encountered when hunting.

There are five known types of allergies in the dog: contact, flea, bacterial,
inhalant and food. Each has some common presentation in dogs, but they also
have features unique to the allergy. I will cover contact, flea, and inhalant
allergies this month since the “hay fever/flea” season will soon be upon us, and
will save food and bacterial allergies for a future article.

In contact allergy, (the least common type) the reaction is localized on the skin.
Contact allergy may come from reactions to the chemicals in flea collars or to
certain types of bedding, such as straw or alfalfa hay. If the dog is allergic, the
skin irritation and itching will be limited to the points of contact.  It may require
a bit of trial and error to identify what’s causing the allergy, but once identified
and removed, the symptoms should clear up quickly.

When considering flea allergies, the non-allergic dog will experience minor
irritation and mild itching, but he dog that is allergic to flea bites can suffer
greatly and will require an aggressive regimen of flea control and treatment.
Untreated, the allergic dog will lick, scratch and chew to the point of hair loss
and sores, inviting a secondary bacterial infection.  Bare spots and sores from
flea infestation will most often be seen on the rump and behind the ears. The
removal of fleas from the dog and control of fleas in the kennel area is most
critical to successful treatment.  

This is easier said than done in some of the warmer, humid climates of the
South.  When you consider a new generation of fleas is hatched every 14-21
days, even the most diligent efforts can sometimes fall short. Using products
such as Frontline is the best preventative for the suffering of fleabites in all
climates.  For the chronic sufferer, corticosteroids are often used to block allergic
reaction and give some relief, but these treatments are generally brief and
given on an intermittent basis, so they should always be given under veterinary

Inhalant allergies are most common type of allergy seen in dogs and they can
be allergic to some of the same inhalant allergens as humans The most common
of these will include weed and grass pollens such as ragweed and Bermuda,
and tree pollens such as cedar, ash, oak, etc. Molds and mildew are also
culprits. Many of these allergies have a seasonal occurrence, such as ragweed,
cedar, and grass pollens and when humans inhale these allergens, they suffer
from respiratory problems including asthma and/or “hay fever”.  Not necessarily
so in the dog, however.

The most common allergic reaction in the dog will still be severe, generalized
itching of the skin.  In fact, inhalant allergies are the number one cause of
itching in dogs.  Most dogs that have inhalant allergy react to several allergens.
If the number of allergens is few and they are the seasonal type, itching may
occur for just a few weeks one or two periods of the year.  If the number of
allergens is high or they are also allergic to substances such as mold or mites
that are present year-round, they may itch constantly.  The method of
treatment will depend largely on the length of the dog's allergy season.
Shampoos, anti-inflammatories, and hypo sensitization (allergy shots comprised
of small doses of specific antigens) can individually or combined provide some
relief to the inhalant allergic dog.  

There may be contraindications to some treatments such as corticosteroids, and
the age and general health of your dog should be considered, so it’s important
that allergy is identified and the course of treatment be administered by your
Allergy is one of the most common conditions
affecting dogs. The most common symptom is
itching of the skin, either localized or generalized
(all over the dog).

Allergies may also involve the respiratory system
and the digestive system.  In the respiratory
system, coughing, sneezing, and/or wheezing
may occur. You may also notice a nasal or ocular
(eye) discharge. Allergies affecting the digestive
may present vomiting or diarrhea.  The dynamics
of allergies work this way; when exposed to
allergens or antigens, (foreign substances) the
dog's immune system overreacts and you get the
symptoms as mentioned.