Cat & Dog Health • Symptom Guide

Why does my pet smell bad?

A persistent odor is often a clue to where a health problem is occurring. The mouth, ears, skin, anal sacs, urine, and wounds are common sources.

Veterinarian reviewedUpdated Aug 20, 2026
The key takeaway

Masking odor with shampoo or fragrance does not treat dental disease, ear infection, dermatitis, or anal sac disease.

Mouth odor

Persistent bad breath commonly accompanies dental plaque, periodontal disease, painful teeth, or oral inflammation. Sweet, chemical, or unusually strong odors can occasionally occur with systemic illness and should be interpreted with other signs.

Ear odor

A yeasty or foul ear smell, especially with head shaking, scratching, redness, or discharge, can indicate otitis. Ear disease may involve yeast, bacteria, mites, allergy, or foreign material.

Skin and coat odor

Greasy skin, redness, hair loss, recurrent hot spots, or a musty odor may occur with bacterial or yeast overgrowth, allergy, parasites, or moisture trapped in skin folds.

Anal or urinary odor

Anal sac disease may produce a strong fishy smell. Urine odor on the coat can result from incontinence, urinary disease, mobility problems, or grooming difficulty. Locate the source before choosing a treatment.