Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Xerostomia, or dry mouth, is uncommon in dogs. It’s most often caused by dehydration, certain medications (such as some antihistamines and sedatives), radiation therapy to the head, or immune-mediated conditions that affect the salivary glands, sometimes along with dry eye. Dry mouth can lead to bad breath, dental disease, and trouble eating, so it’s worth a vet check.
Signs
- Sticky or tacky gums
- Thick, ropy saliva
- Bad breath
- Difficulty chewing or swallowing dry food
- Licking lips or drinking more
Causes
- Dehydration from vomiting, diarrhea, heat, or illness
- Medications with drying effects
- Radiation therapy
- Immune-mediated disease, sometimes with dry eye
- Nerve damage affecting salivary glands
Management
- Treat dehydration and the underlying cause
- Review medications with your vet
- Moistened or wet food
- Fresh water always available
- Regular dental care
- Pet-safe oral moisturizers if your vet recommends them
See a vet urgently if
- Signs of dehydration: lethargy, sunken eyes, dry gums
- Vomiting or diarrhea
- Not drinking
Sources
- Merck Veterinary Manual: Salivary gland disorders in small animals
- Merck Veterinary Manual: Keratoconjunctivitis sicca
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.