How to Treat Itchy Pets

The Pet Doc is our column for pet owners and pet lovers alike. Each week, Dr. Kane will discuss health and environmental issues that affect your pet. If you have any questions, please contact Dr. Kane by clicking "email the author," and he will try to answer them right here in this column.

One of the most common problems in our pets is excessive self-scratching, licking, chewing, and rubbing. These often troublesome signs are usually due to itchiness, a tingling/irritating sensation in the skin, all too familiar to us humans.  

While often attributed to normal pet grooming behavior, most cases are due to some underlying skin problem. Some signs of grooming and itchiness do overlap, but if excessive and/or causing visible skin changes, it is not normal. In addition to scratching, licking, chewing, and rubbing, the signs to indicate more than just normal grooming behavior are:

• hair loss: often on the paws, the side of the body, and the tail base area

• red, irritated skin areas, including raw/moist areas known as hot spots, scratch marks called excoriations, little rash bumps called papules, and general redness of the skin indicating general dermatitis

• crusts and pustules: often signs of secondary infections

• hives: small skin swellings suggestive of an allergy-caused itchiness

• bad coat condition: dandruff, rough coat, dry, greasy/oil

There are many reasons why your pet may be itchy, and each pet reacts differently to different causes.  In mild cases, your pet is likely somewhat irritated by the nuisance of the itch. In severe cases, your pet can become extremely depressed and suffer miserably from the horrible fire-like sensation of their itchiness. There are many common causes that make are pets itch.

Allergies are the most common causes for itchiness. The allergies that affect our pets the most are environmental allergies (atopy), flea allergies, and food allergies. In some pets, certain stimuli cause over-exaggerated immune responses in their bodies, leading to the sensation of itchiness in the skin. These stimuli can range from environmental factors such as pollens and molds, dust mites, and grasses/trees (among many others); insects such as fleas and mosquitoes, whose saliva is sometimes allergy inducing; and food ingredients from beef to chicken, wheat, and soy (among many others).

Another cause is ectoparasites which include any life-form that like to land, travel, migrate, burrow, or feed on/through your pets' skin. Most commonly, fleas, ticks, mites (scabies, especially), and mosquitoes, which leads to itchiness directly through their irritating bites. In addition, internal parasite and hookworm larvae often penetrate skin to find their way to their ultimate destination of the intestines, and that skin penetration can lead to varying degrees of itchiness.

Skin infections, such as bacteria, yeast and fungus are often itchy but are most commonly secondary to allergies; therefore, the itch from the allergy comes first, your pet scratches and licks and a secondary infection occurs, which itself then adds to the overall itchiness. Fungal infection of the skin (usually ringworm) may occur as a primary problem or secondary to other problems.

Problems with the colon/anal region, such as colitis, gastrointestinal protozoal infections, anal gland problems, and parasites can often lead to signs of itchiness in that area. Some types of skin tumors (especially mast cell tumors) can often lead to variable degrees of itchiness.

Treating itchiness relies on two approaches: getting the itchiness quickly relieved, and treating the underlying causes to try to prevent a return of the itchiness. These are not always easily achievable. In mild cases, therapy may not always be required, while in severe cases, a long list of medications and other therapies may be absolutely needed for relief. And even when relief comes, often it is just temporary and not complete. Through a combination of education, therapy and commitment, many pets can be helped. Always check with your veterinarian before beginning any new therapy.

Systemic glucocorticoids (steroids) is a class of drugs that includes the commonly known prednisone/prednisolone, widely used internal medications (oral, injectable) that almost consistently helps reduce itchiness in dogs and cats

Antihistamines (drugs such as Benadryl and chlorphenaramine) can sometimes be helpful in reducing itchiness.  They are probably better at preventing an itch from returning in the cases of mild environmental allergies (atopy). In addition, fish oil pills are widely used it itchy pets, and their overall contribution to itch relief ranges from none to some.  

Topical bathing therapy can only help. Many shampoos and conditioners are available, some with steroids, some without, to help alleviate itchiness and the secondary skin problems associated. In some cases, bathing several times a week is required to help alleviate signs.

Other topicals, from flea and tick control to drops, may be used to help maintain a protective skin barrier.

Your pet can develop an allergy to any ingredient in any food they eat. To limit the chances of this developing, try to limit what you feed your pet.  When we try to diagnose and treat food allergic pets, we encourage feeding one food product that contains either very limited, often novel ingredients, or 'hypoallergenic' diets.  This new diet, free from any other food sources, should be fed for 3 months to decide if a food allergy exists and can be treated with this new food.

If your pet is reacting to environmental stimuli and you can detect which plant/grass/other is causing your pet to have an allergic reaction, do whatever you can to avoid those areas with your pet.  If they do come into contact with known allergy triggers, and even if you don't know what exactly is setting it off, wipe your pet down with a washcloth before coming inside. 

In cases of environmental allergies (atopy), a skin and/or blood test can be performed to determine if and what your pet is likely allergic to.  If the test is positive for allergies, a special vaccine-like injection can be formulated. This de-sensitization requires expense, time, and patience, as the injections are given at home and on a long-term basis, and not every pet responds with dramatic reduction in their itchiness. But it can be a valuable diagnostics and therapeutic tool in the fight against environmental allergens and the resultant itch.

Talk to your veterinarian if your pet exhibits the signs of itchiness discussed here.