What Is a Sialocele?
A sialocele, also called a salivary mucocele, is a collection of saliva that has leaked from a damaged salivary gland or duct into the surrounding tissue. The body walls it off, creating a soft, painless, fluid-filled swelling. It is the most common salivary gland problem in dogs and is seen less often in cats.
Types by Location
- Cervical: a swelling under the jaw or on the upper neck, the most common type
- Sublingual (ranula): a bulge under the tongue on one side of the mouth
- Pharyngeal: swelling in the throat that can affect breathing or swallowing
- Zygomatic: swelling near the eye that can push the eye forward
Causes and Risk Factors
Often no clear cause is found. Suspected triggers include trauma to the neck, chewing on sticks or other objects, and choke-chain injuries. Breeds such as German Shepherds, Miniature Poodles, Dachshunds and Australian Silky Terriers appear to be affected more often.
When it is urgent
A swelling in the throat that causes noisy breathing, gagging or trouble swallowing needs a vet the same day.
Diagnosis and Treatment
- Vets drain a small sample with a needle: thick, stringy, sometimes blood-tinged fluid points to saliva
- Draining alone usually gives only temporary relief because the leak keeps refilling the pocket
- Surgical removal of the affected mandibular and sublingual salivary glands is the usual long-term fix and has a good success rate
- A ranula may be treated by opening and draining it into the mouth (marsupialization), often along with gland removal
Other neck and mouth swellings can look similar, including a seroma, an abscess or a tumor, so a proper exam is important. Dental problems can also cause swelling and drooling; see dog dental disease.
Frequently Asked Questions
Is a sialocele painful?
Usually not, unless it becomes infected or is large enough to interfere with eating or breathing.
Will my dog miss the removed salivary glands?
No. Dogs have several pairs of salivary glands, and the remaining glands produce plenty of saliva.
Can it come back?
Recurrence is uncommon after the correct glands are removed, but it can happen if the wrong side is treated or tissue is left behind.
If you notice a soft swelling under your pet’s jaw or tongue, have it checked. Find a veterinary clinic near you for an exam.