A couple things could be causing your dog's problem.
One likely candidate is some sort of parasite. Parasites can cause hair loss and itching, and often the itching causes the dog to break the skin or irritate the skin. Infections can also result from the scratching, or from the introduction of bacteria into the skin from the actual parasite. Some parasites, like those involved in demadex, actually live in the hair follicle, resulting in thin patches and irritation.
Parasites can be difficult to treat at home, and they're best handled with a drug called Ivermectin that can be injected or given by mouth at your vet. It's usually administered twice, about 10 days apart to ensure that the lifecycle of the parasites is broken.
When you visit the vet, they'll take a scraping of your dog's skin cells, which are then examined under the microscope and the vet can then determine what, if any, parasites are present.
Another possibility could be some sort of infection -like a yeast infection. You'll usually see small red bumps, dryness and a roughness to the skin's surface and oozing. But these are typically VERY itchy, so if you don't see any itching, I wouldn't imagine that this is a likely cause.
An allergy could also be triggering these problems, but again, this is something that would likely be associated with itching, which then in turn causes the dog to scratch and hair loss results.
The allergy could be the result coming in contact with a substance that triggered the allergy, a form of dermatitis.
Some common irritants for contact dermatitis include laundry detergents, floor cleaners and other household chemicals. Your dog can also develop a food allergy, but with a food allergy, you typically see the effects throughout the body, not just one area (but there's always exceptions!) And remember, allergies are tricky, because your dog can develop an allergy at random. So he may have been okay with your laundry detergent one week, and the next, he may have developed an allergy. Some allergies will result in symptoms for several days after exposure to the irritant, and there's always the possibility that the dog is still being exposed to the irritant.
If you suspect this could be the case, you can give your dog some Benadryl (providing she's on no other meds. If he is, check with your vet first). I prefer the dye-free children's liquid Benadryl. For a dosage, you can give 1 mg per 1 pound of body weight, given every eight hours (three times a day). If you decide to use the pills, you can stick them in peanut butter or cream cheese - I've found that this is the easiest way to get our pets to take pills! And if the dog responds well to the Benadryl, and she improves, then there's a very good chance that it's an allergy that's to blame.
Also, if your dog has any areas that are open wounds or sores, you'll want to keep those areas clean until they heal up. Once a day, you'll want to wash the area with a bit of antibacterial soap. Twice daily, you can clean the area using betadine (found in the first aid section of the drug store), allow this to air dry and then put a dab of neosporin or antibiotic ointment on the wound. This will help stave off infection and healing can occur.
For more information on mites, ringworm, parasites, allergies, and more visit:
I hope your dog is feeling better soon! Don't hesitate to let me know if you have any additional questions.
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