Why is my chihuahua losing hair on her head with scaly skin and sores?

Poor Chica! This could be caused by a number of different things. Some common possibilities would include a localized bacterial or fungal skin infection, an allergy, or even an inflammatory reaction to an insect bite or something similar. Treatment will depend on what the underlying problem is, so it would be best to have this checked by your vet when you are able to. He/she can do some simple skin tests to help diagnose the problem and get her started on appropriate treatment.

These symptoms can be from a yeast infection of the skin. I suggest you try to use this medicated shampoo on her. Lather the shampoo, let it sit on her for 10 minutes and then rinse. In between baths you can use this medicated mousse. I recommend you bathe her twice a week. ( https://www.allivet.com/p-6692-douxo-chlorhexidine-shampoo-for-dogs-and-cats.aspx?SearchTerm=chlorhex+Auto ) ( https://www.allivet.com/p-6673-douxo-chlorhexidine-climbazole-mousse-for-dogs-and-cats-68-oz.aspx )

It sounds like there are few things that could be going on with Belle. She could be in pain with the yelping. The hair loss and chewing could be due to fleas, mites, ringworm, or allergies. If she isn't up to date on her flea treatment, I can give you one for her. First, I would give her Capstar. It's a one time pill that starts killing fleas within 30 minutes. Then follow up with a spot on treatment, such as Advantage or Revolution. This is a treatment that has to be used once a month. You will also have to disinfect the environment. Wash her bedding in hot soapy water, and vacuum the furniture and carpet surfaces. You can use a spray to kill fleas in the house, such as Indorex, or a flea bomb would work well to kill the fleas in the home. If she is up to date on her flea treatment, I recommend taking her into the vet for an exam tomorrow. The vet can do blood tests, skin scrapings, and use a Wood's lamp to diagnose allergies, mites, and ringworm. Once the cause of the itching (chewing is a sign of itchiness) is found, the vet can prescribe the appropriate treatment. I hope this helps!

Thanks for using Petco Pet Education Center, formerly Petcoach! If he is itchy at all then it could be due to allergies. It really comes down to figuring out what is causing his allergies so that they can be treated or the specific allergen avoided. There are many things that can cause allergies though in most cases they can be broken down into 3 big categories: flea, food and environmental allergies. Allergies are usually worked up in a stepwise fashion starting with flea allergies as this is the easiest and cheapest to take care of. If not on a flea preventative, then it would be a good idea to get started on one. If already on one then it would be a good idea to change to something else (there are many new products out in the market). If not improved in 1-3 months then it is time to move on and check for food allergies by switching to a novel diet (new protein and new carbohydrate). If that does not seem to be the issue then you are left out having to check for environmental allergies which require blood and/or skin tests. Allergies can be very frustrating to deal with at first but so rewarding at the end when we are able to treat them effectively!

Thanks for using Petco Pet Education Center, formerly Petcoach! This is possibly due to allergies. It really comes down to figuring out what is causing her allergies so that they can be treated or the specific allergen avoided. A secondary infection is likely and also needs to be addressed. 

There are many things that can cause allergies though in most cases they can be broken down into 3 big categories: flea, food and environmental allergies. 

 Allergies are usually worked up in a stepwise fashion starting with flea allergies as this is the easiest and cheapest to take care of. If not on a flea preventative, then it would be a good idea to get started on one. If already on one then it would be a good idea to change to something else (there are many new products out in the market). 

If not improved in 1-3 months then it is time to move on and check for food allergies by switching to a novel diet (new protein and new carbohydrate). If that does not seem to be the issue then you are left out having to check for environmental allergies which require blood and/or skin tests.

 Allergies can be very frustrating to deal with at first but so rewarding at the end when we are able to treat them effectively!


Hair loss can be caused by bacterial, parasitic or fungal infection, dietary or environmental allergies or sensitivities, immune system disorders, or a combination of the above. I recommend making an appointment to have Pixie seen by your veterinarian to help determine the cause of the hair loss as soon as you can. The vet may want to look at a sample from the areas of hair loss (taken by a procedure known as a skin scraping) and examined under the microscope to determine what kind(s) of infection may be present and to figure out what medication is appropriate for treatment. Good luck!

It is hard to say what is causing Bacardi's problems. The third picture you included looks like pus, which would indicate infection and would need antibiotics to treat. Some dogs can be allergic to fleas, and it may only take 1 bite to make them itchy all over. If you are seeing scabs from where you applied a flea medication or flea collar, it may be irritating the skin so I would recommend removing it and bathing with dog shampoo thoroughly. Causes of itching in dogs include fleas or flea allergies, mites, or skin infection. The hair in the second picture looks like normal shedding to me, but if you feel it is weird for Bacardi, it could be caused by inflammation or from the extra itching she is doing right now. You can try a shampoo like Dechra MalAcetic Ultra Shampoo, but if it doesn't respond in a day or two, Bacardi should be seen by a vet as she may need oral medications to control the itching.