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My senior dog has black mouth crusts. What's the cause and treatment?

Updated on September 23, 2025

Pet's info: Dog | Jack Russell Terrier | Male | neutered | 18 lbs

Hello! My senior Jack Russell has developed black crusts around his mouth, particularly on one side where he sustained a cut from another dog earlier in life. He has dealt with food allergies in the past, but recently seemed to have found a good combination that quelled other symptoms. The crust doesn't seem to hamper him much, but he does scratch them and that can cause them to break and bleed. What could be the cause? Are the options aside from steroids for treatment?

1 Answer

Most Helpful Answer

Published on March 8, 2019

Given history and signs, this is likely to be caused once again by an allergy and secondary infections. A check up would be needed to confirm this clinical suspicion and treat appropriately.
Disinfection can eventually be started at home with very diluted hibiscrub or betadine or salted water baths. Buster collar may be useful as well to avoid any scratching.
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