How to Deal With Itchy Skin in Dogs

Killing fleas, airing and brushing the coat, and getting rid of the dirt, dander and pollen on your dog, are all key to keeping your dog's skin healthy and happy.

Veterinarian Marty Becker details the newest thinking about dogs with chronic itchy skin:

Many dogs with itchy skin and recurrent bacterial infections have a weakness in their skin known as a "barrier defect.'  In normal dogs, the skin's barrier keeps water inside the body and substances like bacteria, yeast and pollens out. In dogs with a barrier defect, those substances "leak" into the deeper layers of the skin. Because the body perceives them as invaders, the immune system revs itself up to destroy them, bringing local inflammation to the area as part of the immune response....

The good news is that there’s a solution to this problem. The even better news is that it’s not costly, and the side effects are few to none."

Becker goes on to note that the solution, or recommended course of treatment, is weekly or even daily baths and topical treatment.

I have noted in the past that weekly baths are key to terrier coat health -- the opposite of what many show dog folks will tell you.

I have had terriers for 45 years and, with one or two small and very short-lived exceptions, I have never had a dog with itchy skin.

Why is that? 

I chalk it up to two simple factors:

1. I prefer mutts, cross-breeds, and unregistered dogs. 
   One of the main reasons we have a lot of skin problems in dogs, and especially terriers, is that most show dogs are heavily inbred and, as a consequence, they have weak immune systems and more allergies.
   
   
2. I wash my dogs every week. 
   I have always washed my dogs once a week, and you should too.  You have heard that washing your dog is "bad" for the dog?  Nonsense.  A dog wants to be clean and it deserves to be clean. You wash yourself at least once a week, right?  Do the same for the dog.  If you are worried about keeping your dog's coat shiny for shows, please grow up and get a life.  A dog does not want a ribbon -- its want to be free of itch.

So why do dogs get itchy skin? 

There's a lot of veterinary mumbo jumbo on that score, but let's cut to the chase and lump up the three factors:

1. Weak immune system and auto-immune disorders. 
   Dogs can get allergic to pollen and even to their own dandruff, which is one reason you want to wash your dog -- to reduce pollen and dander as well as dirt. Yes, some dogs have food allergies, but this is much less common than most people think, and the most common diet-based allergy in dogs is not to corn or wheat, but to beef.  If your dog has seasonal hotspots, it is almost certainly not due to a food allergy, but to a reaction to pollen, dander, and fleas.
   
   
2. Allergies to fleas, mites, ticks, and mosquitoes. 
   Flea bite dermititis is common, and it only takes one or two fleas for a dog with a weak immune system to go a little nuts.  One reason to wash your dog with flea shampoo once a week in spring, summer and fall, is to make sure your dog harbors few or no fleas, mites, or ticks.
3. Dogs have too much hair these days.
   Air circulation over the coat and the skin helps cut down on fungus infections. When thick hair is combined with poor hygiene (too little bathing and too little combing), the ground is set for canine skin trouble.  Again, washing your dog and combing out the under-thatch at least once a week will solve a lot of problems.

Do you need a special shampoo to wash your dog? 

No. 

The folks who claim otherwise are marketing nonsense or repeating old wives tales.  If a shampoo is gentle enough to be used on a human head once a day, it's fine for a dog once a week!

In cold-weather months, when fleas and ticks are not much of an issue, use the cheapest shampoo you can find at the grocery store.  I get Suave at about $1 a bottle, and it works fine.  Expensive non-medicated dog shampoos are all hype and marketing.  Save your money.

In summer, I use an off-the-shelf pyrethrin-based flea and tick shampoo ($4.00 a bottle on the Internet and $7 at the store), and I make sure to lather well around the ears and neck, and around the dog's vent area. 

Pyrethrin is a very safe, old, and natural insecticide made from Chrysanthemum flowers, and pyrethrin-based shampoos are famously effective at killing fleas and ticks. In doses too small to kill fleas and ticks, pyrethrin repels them, and the the active ingredient is biodegradable as well.  The US Department of Agriculture says pyrethrins are "probably the safest of all insecticides" and has approved their use around foodstuffs and at food plants. 

Killing fleas, airing and brushing the coat, and getting rid of the dirt, dander and pollen on your dog, are all key to keeping your dog's skin healthy and happy.

Do you already have a dog with itchy skin, aka a "hot spot"?

If it's a seasonal hot spot, as is so often the case, then it almost certainly has nothing to do with a food allergy, and is more likely to be due to pollen, dander and (especially) fleas. 

Wash your dog, treat for fleas, and knock down the initial itchiness with a dose of benadryl (2 mg or less per pound), and things should sort themselves out fairly quickly.

After the fleas are gone from the dog, and eliminated from its bedding as well, I generally recommend washing dogs that have skin problems with a human dandruff shampoo like Selsun Blue. 

If the seasonal hot spot problem continues (probably due to pollen) the dog should also get dosed with benadryl (up to to 2 mg per pound of dog, every 12 hours) to reduce itching.  Remember:  people take benadryl for their allergies all the time, and dogs can take it too if it is administered in the proper dose (not for cats!).  For terriers, the 25 mg. benadryl caplets sold at Walgreen's as a "sleep aid" for humans are just about perfect.

Of course not all "hot spots" can be eliminated with a good shampooing alone.  There is a chance your dog might have a fungal skin infection, aka, "ring worm."

The cheap over-the-counter remedy here is to treat the red or balding areas with a topic fungal ointment like Tenactin or its generic equivalent. Rub it into the root of the hair and the skin. This ointment is the same ointment used to treat athlete's foot and jock itch, and is sold at any pharmacy or grocery store for about $7 a tube.

Another step that may be necessary, especially if the dog has already rubbed the skin raw, is to dose the dog with an antibiotic like cephalexin (sold without prescription as "Fishflex") until the skin heals up.  A 7-day course of antibiotics will help the dog "attack the attacker" from the inside, as well as the outside.

If you suspect mange, wash the dog and bedding with a pythrethin-shampoo, and dose the dog at the mange site with a dilute (.05 percent) solution of Ivermectin as well. 
.