When Dogs and Cats Itch: Pruritus

Pets and itching. They seem to go hand in hand like cats and meowing or dogs and barking. But itching can be a sign of a problem that needs attention. Specifically, insect parasites or allergies can cause a sensation that leaves pets with an uncontrollable desire to scratch; this is referred to as pruritus. Cats and dogs have a threshold of pruritus (sometimes called “itch threshold”) that allows them to tolerate a certain amount of discomfort. When the discomfort gets too severe, however, they begin to scratch. Several factors can affect whether or not dogs or cats can resist scratching including the specific irritant, boredom, other physical sensations, or anxiety.

Cause

Many skin diseases can cause or can contribute to pruritus. Pets may actually have two or more skin conditions at the same time, which makes itching worse. Allergies are the most common source of pruritus with flea allergies, atopic dermatitis, and food allergies seen most frequently. Parasitic insects (such as mites, fleas, lice, and ticks) and infections can also cause itchiness. In some cases, pets cause the itching themselves by constantly licking one area of the skin over and over again.

Symptoms

Itchiness may manifest as a prickling feeling in one specific place or it might come on as a burning sensation. Skin is often red and irritated from the scratching and there may be lesions, hair loss, or scaling that result from your pet constantly rubbing, scratching, and biting the area that itches.

Other signs vary according to the cause of your pet’s pruritus. In the case of insect parasites, you may find raised bumps (bug bites) or be able to see the insects themselves on your pet’s skin and coat.  In the case of allergies, they may only appear seasonally at first, but if not properly treated, your cat or dog could end up with a year-round condition. Pets with atopic dermatitis are also at risk for ear canal infections.

Treatment

Flea collars and other methods of flea control can be tried as soon as soon as you notice your pet scratching. If the itchiness seems to persist despite these therapies, you should see your vet to look for other possible causes of pruritus.  Your veterinarian will examine your pet and take a dermatologic history in an effort to locate the source of the itchiness.

With allergies, antihistamines (such as Hydroxyzine) may be prescribed. Fatty acid supplements are sometimes used to enhance the effectiveness of antihistamines. Cortisone may be administered in pill, shot, spray, or cream form to ease itching and irritation (you may need to use an Elizabethan collar when administering cream to ensure your pet doesn’t lick the medication off right away). Some pets may also be given immunotherapy shots to reduce their hypersensitivity towards common allergens.

In the case of some parasitic insect infestations, you may need to use insecticides, but do so carefully since these can be poisonous to pets.

This information is for informational purposes only and is not meant as a substitute for the professional advice of, or diagnosis or treatment by, your veterinarian with respect to your pet. It has, however, been verified by a licensed veterinarian for accuracy.