Pets are present in over half of all households and having a household pet is especially popular in the developed world, with cats and dogs the two most commonly chosen pets. However, allergies to material shed from a pets body can be a dampener for some.

Causes of pet allergies

Animal allergens are protein molecules shed by an animal that cause an allergic reaction in some people. While most people do not react to these molecules, those with an allergy may have an immune response that triggers an allergic reaction on encountering the allergen. Common allergens shed by pets in the house include saliva, fur, dead skin, urine and sebum.

Symptoms

Symptoms of pet allergies are similar to those of other allergic reactions and may occur after handling a pet or even just on entering a home where pets reside. Symptoms include:

• Allergic rhinitis or runny nose
• Allergic conjunctivitis or red, watering eyes
• Exacerbation of asthma causing wheezing, breathing difficulty and a tight chest
• Skin irritation leading to itchy rashes and blisters

Prevention

There are several measures people can take to reduce the presence of pet allergens and minimize allergic reactions. These include:

• Avoiding furnishing the home with carpets and soft furry upholstery or curtains that may trap animal hair. Instead hardwood floors and blinds should be used. Woollen clothes should also be avoided as much as possible.
• The pet litter tray should be kept away from any vents and natural ventilation should be allowed each day. Areas or rooms where the pet sleeps, plays or feeds should be kept meticulously clean.
• After handling pets, hands should be washed thoroughly with soap and care should be taken not to touch the face, nose, mouth or eyes with unwashed hands.
• Bedrooms and living rooms should be made pet-free areas if one of the family members is allergic.
• Routine checkups at the vet's are also important.

If the animal is removed from the home due to potential allergies, the allergen still remains in the home for around six months or more.

Diagnosis and treatment

Diagnosis of pet allergies is made based on details of the symptoms that manifest on exposure to pets. A skin prick test or radioallergosorbent test ((RAST) may also be used to test for a pet allergy in people who have more than one allergy.

When an allergic reaction occurs, long acting, non-seditative antihistamine or nasal sprays containing steroids can be used. Examples of antihistamines include levocetirizine, loratadine and azelastine. People who develop asthma may benefit from taking the leukotriene receptor antagonist montelukast.