Petco Text Logo
Petco Pet Logo
  • Two Easy Ways to Start Earning Rewards!

    rewards header
    Become a member today!
    Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
    Petco Pay LogoBecome a credit card member today!

    Earn 2X Pals Rewards points at Petco
    when you use Petco Pay!

    APPLY NOW
    Learn More About Petco Pay Benefits

Why does my dog have black skin spots? Allergies, fleas, or infection?

Updated on September 23rd, 2025

Pet's info: Dog | Wire Fox Terrier | Female | spayed | 9 years and 9 months old | 20 lbs

Hello, I have a Wire Hair Fox Terrier who has awful allergies. Her skin seems to have a black coating, for lack of a better word, on several spots of her body. Is this common for types of fleas, mites or skin infections?

3 Answers

Most Helpful Answer

Dr. Leigh, DVM

Answered By Dr. Leigh, DVM

Veterinarian

Published on January 15th, 2017

She could have a skin infection, mites, fleas, ringworm, allergic dermatitis, etc. Your vet can do a skin scrape, cytology, or culture to help diagnose and then prescribe medications to treat the problem. She may need an antibiotic, anti-histamine, corticosteroid, or other medications depending on the cause. Make sure to treat her with a monthly flea medication like NexGard, Frontline, Advantage, or Revolution to prevent fleas.
Vote Icon1Pet Parents found this answer helpful

Related Answers from Veterinarians

  • Answered By Debi Matlack

    Veterinary Technician

    Published on December 6th, 2016

    Skin problems can have a variety causes. Fleas or other insects can cause irritation that can persist even after the fleas are gone. Treating the environment for fleas is also vital in eliminating the problem. Other causes for skin trouble can include bacterial or fungal infections and allergies to environmental substances and/or food. A dog may have a little sensitivity to some of these but not show any symptoms until they are confronted by several at once. Ideally, I would get your dog in to see the vet for an exam. Your vet may suggest a food trial with a food that has a novel protein source, one that your dog has never been exposed to, such as venison or duck. Proteins in food are the primary reasons for food allergies to occur in dogs.

    Vote Icon

    1Pet Parents found this answer helpful

  • Answered By Jenny, DVM

    Veterinarian

    Published on January 26th, 2018

    make sure you are on proper flea control and this is not part of the problem. I would give a weekly bath in a medication shampoo to loosen up debris. I would also have your vet check they thyroid and check for a yeast infection that can make this problem worse.

    Vote Icon

    1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share

Styled arrow button