Itchy skin caused by allergies commonly affects pets. Pet allergies can’t be cured, but once the underlying cause has been identified, our Smithtown Animal Hospital team can devise an effective management strategy. We provide information about pet allergies to help relieve your pet’s itchiness.

Common pet allergies

Pets can experience an allergic reaction to any environmental pest or substance, but common allergy instigators include:

  • Fleas — The most common pet allergy is flea allergy dermatitis (FAD). Affected pets are allergic to a protein in the flea’s saliva, and a single flea bite can lead to severe itchiness for up to two weeks.  
  • Environmental allergens — Environmental allergens, such as pollens, mold spores, and dust mites, can trigger an allergic reaction. Affected pets often have recurrent or chronic ear, skin, and anal gland infections.
  • Food — Pets can be allergic to food ingredients, most commonly proteins such as chicken, dairy, beef, and eggs. Food-allergic pets also often suffer recurrent or chronic ear and skin infections.

Many allergic pets have more than one trigger, and determining the cause of their itchiness can be a long, involved process. 

Pet allergy diagnosis

Diagnosing the cause of your pet’s itchiness can be complicated. Potential diagnostics include:

  • Looking for fleas — Since FAD is the most common pet allergy, our hospital team will first evaluate your pet for fleas, but not finding a flea does not rule out FAD. Many pets with FAD groom excessively and remove the fleas from their coat, so we also look for flea dirt (i.e. flea feces) in their coat.
  • Evaluating lesion location — In some cases, your pet’s lesion distribution can help determine the triggering factors. For example:
    • FAD typically causes hair loss and skin lesions (e.g., bumps, sores, or raw skin) on the pet’s lower back, inner thighs, and abdomen.
    • Environmental allergens typically cause hair loss and skin lesions around the pet’s eyes and mouth, on their paws, abdomen, and under their tail.
    • Food allergies typically cause hair loss and skin lesions on a dog’s face, feet, and under their tail, and on a cat’s head and neck.
  • Assessing history — Your pet’s history also can help determine their triggers. For example:
    • Is your pet itchy seasonally or year-round? — Seasonal itchiness usually indicates environmental allergens.
    • Do your pet’s signs get worse after eating a particular treat? — This could indicate a food allergy.
    • Does your pet have gastrointestinal (GI) signs in addition to their itchiness? — Food allergies sometimes cause GI signs in addition to dermatitis.
    • When did your pet’s signs start? — Pets typically manifest environmental allergies between 1 and 3 years of age, and food allergies before 6 months or after 6 years of age. 
    • Is your pet on year-round flea prevention? — FAD is often suspected if your pet doesn’t receive year-round flea prevention.
  • Skin scraping — We collect a skin sample so our team can assess your pet’s cells microscopically for abnormalities.
  • Culturing — Many allergic pets have secondary bacterial and yeast infections, and we may need a culture to determine the causative pathogen and best antimicrobial to use.
  • Biopsying — We may need to evaluate the deeper layers of your pet’s skin to determine a cause.

Flea allergy dermatitis management in pets

The only way to manage FAD is to eradicate all fleas on the pet and from their environment. Management strategies include:

  • Flea prevention — The affected pet, as well as all household pets, should receive year-round flea prevention.
  • Bathing — Once flea prevention is absorbed (i.e., after 48 hours), bathing the pet can help remove fleas and flea dirt and soothe itchy, irritated skin.
  • Environmental control — To remove fleas from the pet’s environment:
    • Wash all bedding at a high temperature.
    • Sweep and vacuum your floors, and discard the vacuum bag.
    • Treat home surfaces using an appropriate insecticide.
    • Treat your yard with an appropriate insecticide.
    • Repeat these steps until all fleas at every life stage are exterminated.
  • Medications — We may recommend anti-itch medications to help alleviate your pet’s itchiness until their reaction subsides.

Environmental allergen management in pets

When our team suspects environmental allergens, we will recommend allergy testing to determine the causative factors. Management strategies include:

  • Bathing — Removing allergens from your pet’s skin can help reduce their signs. Between baths, wipe down your pet’s coat with moist towels.
  • Reducing exposure — When possible, limit your pet’s exposure to the causative allergen. Recommendations include:
    • Keeping your pet indoors when you mow the lawn
    • Keeping your doors and windows closed
    • Running your air-conditioner whenever possible
    • Dusting, sweeping, and vacuuming often to remove dust mites
    • Washing your pet’s bedding frequently
  • Anti-itch medications — Steroids and non-steroidal anti-itch medications are typically needed to help control a pet’s environmental allergies. 
  • Antimicrobials — If your pet has a secondary infection, we will prescribe an appropriate antimicrobial to clear the infection.
  • Hyposensitization therapy — Allergy shots, which are the best treatment for environmental allergies in pets, involve using the allergy testing information to produce injections, and gradually administering increasing allergen doses to the pet to desensitize them to the problematic substance. Most pets respond well to this treatment, but results can take 6 to 12 months. 
  • Omega-3 fatty acids — Omega-3 fatty acids can help reduce skin inflammation and itchiness.

Food allergy management in pets

The most effective food allergy management is to avoid the problematic ingredient that a food elimination trial has identified as the cause. The trial involves:

  • Feeding a hypoallergenic diet — You must feed your pet a hypoallergenic diet for about eight weeks. You can choose a diet containing a novel protein, such as kangaroo, bison, or venison, or a hydrolyzed diet with broken down protein that the body no longer recognizes.
  • Staying vigilant — To ensure a successful trial, your pet must eat only the trial diet during the eight-week period—meaning they can’t have treats, table scraps, or medicated chews or supplements.
  • Reintroducing ingredients — If your pet’s signs improve on the elimination diet, you can challenge them with ingredients from their previous diet to determine the triggering food.
  • Avoiding the food — The best management for food allergic pets is to avoid the causative ingredient.

If you suspect your pet has an allergy, contact our Smithtown Animal Hospital team, so we can determine the cause and alleviate their itchiness.