Two Easy Ways to Start Earning Rewards!
Become a member today!
Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
Become a credit card member today!Earn 2X Pals Rewards points at Petco
when you use Petco Pay!APPLY NOWLearn More About Petco Pay Benefits
My dog has hair loss on his rear, no itch or redness. What's wrong?
Updated on September 23rd, 2025
Pet's info: Dog | Mixed Breed Large (61lb +) | Male | neutered | 9 years old
My dog has hair loss on his butt and top of his tail. Theres no redness, he doesn’t bite it or itch, and it doesn’t appear to be a ringworm. It’s been like this for a few months now and my other dog hasn’t been affected by it. I’ve also treated it as a hotspot and nothing changed. If anything the skin just looks a bit dry. Should I be worried? Is there anything I can do to help him? (He just recently turned 9)
5 Answers
Most Helpful Answer
Answered By Ricardo Fernandez, DVM
Veterinarian, Veterinary Oncology Resident
Published on March 19th, 2019
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!
1Pet Parents found this answer helpfulRelated Answers from Veterinarians
Answered By Dr. Massimo Orioles, DVM, Cert AVP, MRCVS
Veterinarian
Published on February 11th, 2017
This is probably due to an allergy, although it could also be fleas or mites. First of all, in order to rule out skin parasites, you will need to treat with a high quality flea treatment (advocate or advantage), then get him to the vet to perform a skin scrape - this might reveal an infection or a mite infestation. If all of those came back negative, the next step is to treat the allergy symptomatically and try discovering the cause of the allergy.
1Pet Parents found this answer helpful
Answered By Oneal Bogan, DVM
Veterinarian
Published on October 15th, 2017
Hello.
There are a few things that could be causing the hair loss on Rusty's tail.
Common causes of hair loss are allergies, parasitic mites, self trauma, bacterial infection and endocrine disease. Your vet can test for these things and get to the bottom of the cause. I would start with them doing a physical exam and then going from there.
Best to you and Rusty.2Pet Parents found this answer helpful
Answered By Dr. Elizabeth
Veterinarian
Published on January 3rd, 2020
Rocky's hair loss could be several things including allergies, endocrine disease, parasites, hormonal changes, poor diet or the normal twice yearly shedding of the coat. The only way to figure out the cause is to have Rocky examined by your veterinarian. You can rule out parasites by using an oral medication like Simparica. There are a couple things you can do at home and they can help but they may not address the underlying cause. You can try adding in an omega 3 fatty acid supplement for dogs, this can help improve the skin health. You may also try changing his diet to something like Royal Canin or Nutro as they are aimed at skin health. Best of luck and please feel free to post any additional questions.
1Pet Parents found this answer helpful
Answered By Linda G, MS, DVM
Veterinarian
Published on September 1st, 2017
Hello, & thank you for using Petco Pet Education Center, formerly Petcoach. If you are not using one of the better topical or oral flea preventatives, & you are just relying on a store bought flea collar, then I would not rule out fleas. In sensitive dogs, all it takes is 1-2 fleas to drive them crazy. For all of your dogs to be itching & losing hair, I would also want to rule out sarcoptic mange. This mite is easily spread from dog to dog. And it is possible for all of your dogs to suffer in various ways for environmental allergens. If you can, take the most seriously affected dog to your vet. With a couple of skin tests, most things can be ruled in or out & the proper treatment/medications can be given for relief. Hope everyone is doing well soon. Take care.
1Pet Parents found this answer helpful