Why is my senior dog suddenly losing fur only on his back?

Hair loss can have a variety of causes. One of the first things to determine is whether he is scratching himself in that area or not. Dogs often scratch themselves at night when we are sleeping so it is harder to see. If he is scratching, the hair loss could be due to parasites such as fleas or mites, a bacterial infection, yeast overgrowth, or skin allergies. If he does not seem to be itchy, hair loss can be caused by hormonal changes or certain endocrine diseases. These are just some of the possibilities. In order to determine what is most likely, I recommend taking him to your local veterinarian for a thorough exam and an initial skin test if needed to determine the cause.

Hello. Toby has a type of dermatitis going on, but the underlying cause cannot be determined just from a photo. It could have a bacterial, autoimmune, fungal or even parasitic ( mange mites ) cause. Your veterinarian can use a couple of rather simple diagnostic aids ( skin scrapes, hair plucks, dermatophyte cultures ) to determine the cause of the hair loss & lesions, then the correct treatment can be started to resolve this. Good luck & thanks for using Petco Pet Education Center, formerly Petcoach.

Hi, thanks for using Petco Pet Education Center, formerly Petcoach! Poor Doodles! There can be many reasons for hair loss: bacterial or yeast skin infection, Demodex mites, endocrine disorders (low thyroid, cushings), alopecia x and there is a hair loss condition linked to intact make dogs. I would have him seen for blood work that includes thyroid testing and a skin scraping. Putting dogs on Nexgard or Bravecto can also rule out demodex. I wish you the best

Hi there! Thanks for using Petco Pet Education Center, formerly Petcoach! There is a variety of reasons that can explain alopecia or hair loss. The causes can be differentiated by the clinical signs associated with it and the physical exam findings. If Wally is only showing some hair loss without scratching or overgrooming then it could conditions such as alopecia areata that can affect dogs and usually resolves on its own. If there is evidence of scratching and you start noticing some redness or irritation associated with it, then other conditions such as allergies are possible. If you notice him overgrooming himself in that area then it could be something like psychogenic alopecia which is more of a behavioral issue. I think that since he is not having overt clinical signs and it is mostly hair loss, I think it is possibly transient and could resolve on its own. You can monitor this closely and if it does not resolve or it worsens then have him examined by your veterinarian. Good luck!

Thanks for using Petco Pet Education Center, formerly Petcoach! This is possibly due to allergies. 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!

Hi there! Thanks for using Petco Pet Education Center, formerly Petcoach! There is a variety of reasons that can explain alopecia or hair loss. The causes can easily be differentiated by the clinical signs associated with it and the physical exam findings. If Frida is only showing some hair loss without scratching or overgrooming then it could conditions such as alopecia areata that can affect dogs and usually resolves on its own. If there is evidence of scratching and you start noticing some redness or irritation associated with it, then other conditions such as allergies are possible. If you notice her overgrooming herself in that area then it could be something like psychogenic alopecia which is more of a behavioral issue. I think that since she is not having overt clinical signs and it is mostly hair loss, I think it is possibly transient and could resolve on its own. You can monitor this closely and if it does not resolve or it worsens then have her examined by your veterinarian. Good luck!

It looks as if your dog has a skin infection, most commonly caused by an allergy, a skin mite (Demodex) or fleas. 

The allergy could be a due to a protein in your dog’s food or an environmental allergy like to dust, pollens, grasses, etc. 

The allergy causes your dog to itch and chew at the skin which breaks down the skin barrier. This then leads to infection. Skin infections are typically characterized by large areas of hair loss, redness, crusting, flaking, and pustules. A thorough skin examination by your veterinarian should be able to determine the cause of the itch so it can be treated appropriately. Your dog will most likely need antibiotics to help clear up the infection and possibly an allergy/anti-itch medication like Apoquel, Atopica, or Cytopoint to give some relief while the infection clears up. A medicated shampoo may be beneficial as well. I would also recommend he be on a good flea control routinely too. Once the infection has resolved a long term allergy medication (like Apoquel or Cytopoint) can be given on a regular basis to prevent any future problems. I hope this helps. Thanks for using Petco Pet Education Center, formerly Petcoach. Best of luck.