A salivary stone is a hard, mineral deposit that forms inside a salivary gland or its duct, blocking the flow of saliva. These stones affect roughly 1.2% of the general population and are the most common cause of salivary gland swelling. Most are small, but even a pea-sized stone can cause sudden, intense pain during meals.
Why Stones Form in Salivary Glands
Your mouth has three pairs of major salivary glands that produce saliva to help you chew and digest food. Salivary stones develop when minerals in your saliva, primarily calcium and phosphate, crystallize around a core of organic debris like dead cells and proteins. The stone grows in layers over time, much like a pearl forming inside an oyster. Other minerals found in these stones include magnesium, iron, copper, and manganese.
The submandibular glands, located beneath your jaw, account for 80% to 90% of all salivary stones. This happens because their ducts are longer, angle upward against gravity, and produce thicker, more mineral-rich saliva than the other glands. The parotid glands (in front of your ears) account for 5% to 20% of cases. Stones in the sublingual glands, under the tongue, are rare.
Common Risk Factors
Anything that thickens your saliva or slows its flow raises your risk. Dehydration is the biggest factor, whether from not drinking enough water, illness, or medications. Diuretics (water pills), antihistamines, and anticholinergic drugs all reduce saliva production and concentrate the minerals that form stones. People with gout or those who have had kidney stones also appear to be at higher risk, likely because their body chemistry favors mineral buildup.
Smoking and a history of salivary gland infections can damage the duct lining, creating rough spots where crystals are more likely to stick and grow. Stones are more common in men than women and tend to show up between the ages of 30 and 60.
What a Salivary Stone Feels Like
The hallmark symptom is swelling and pain in the affected gland that flares up at mealtimes. When you eat, your brain signals the gland to release saliva, but the stone blocks the duct. Saliva backs up behind the blockage, causing the gland to balloon with pressure. This is sometimes called “mealtime syndrome.” The pain and swelling typically last one to two hours after eating, then gradually fade until your next meal triggers the cycle again.
You might also notice a dry mouth, a bad or salty taste, or difficulty opening your mouth fully. Some people can feel the stone as a hard lump under the tongue or along the jawline. Small stones may cause only mild, intermittent discomfort, while larger ones produce sharp, unmistakable pain that makes chewing feel like a chore.
When Stones Lead to Infection
A blocked salivary gland creates a warm, stagnant pool of saliva where bacteria thrive. This can lead to sialadenitis, an infection of the gland itself. Signs include redness and warmth over the swollen area, fever, pus draining into your mouth, and worsening pain that no longer follows the mealtime pattern. Left untreated, the infection can progress to an abscess or, in severe cases, spread into the deep tissues of the neck and compromise your airway. An infected salivary gland that isn’t responding to home care warrants prompt medical attention.
How Salivary Stones Are Diagnosed
A doctor can often feel larger stones during a physical exam by pressing along the floor of the mouth or under the jaw. For confirmation and to locate stones that aren’t palpable, imaging is the next step. Ultrasound is the most common first-line test: it’s painless, involves no radiation, and has a specificity of about 95%, meaning it rarely mistakes something else for a stone. Its sensitivity is around 77%, so it catches most stones but can miss very small ones or those with low mineral content.
CT scans provide more detailed images and are better at detecting stones deep within the gland, though their accuracy depends on how much calcium the stone contains. A specialized X-ray called a sialogram, where dye is injected into the duct, can outline the exact location and size of a blockage but is used less frequently now that ultrasound and CT are widely available.
Treating Small Stones at Home
Many salivary stones pass on their own with conservative measures. The goal is to increase saliva flow and flush the stone out of the duct. Drinking plenty of water throughout the day keeps saliva thin. Sucking on sour candy or lemon wedges stimulates a surge of saliva production that can push a small stone forward. Gentle massage of the gland, pressing from back to front toward the duct opening, helps move things along.
Warm compresses applied to the swollen area for 10 to 15 minutes several times a day can also relax the duct and ease discomfort. Over-the-counter pain relievers help manage soreness. If the gland shows early signs of infection, antibiotics may be prescribed alongside these measures. For many small stones, this combination is enough, and the stone passes within days to a couple of weeks.
Procedures for Larger Stones
When a stone is too large to pass naturally or conservative treatment hasn’t worked, several procedures can remove it without sacrificing the gland.
- Sialendoscopy: A tiny, flexible camera is threaded into the salivary duct through its natural opening in the mouth. The surgeon can grab small stones with miniature instruments or break them apart. This minimally invasive approach achieves complete symptom relief in about 78% of cases on the first attempt, rising to nearly 97% with follow-up procedures. Recovery is quick, with most people returning to normal eating within a few days.
- Incision and removal: For stones lodged near the duct opening, a small cut inside the mouth allows direct access. This is a straightforward procedure often done under local anesthesia.
- Shock wave therapy: Sound waves directed at the stone from outside the body fragment it into smaller pieces that can then flush out naturally. This works best for moderately sized stones.
- Gland removal: If a gland has been damaged by repeated infections or contains a very large, deeply embedded stone, surgical removal of the entire gland may be necessary. This is a last resort, since the remaining salivary glands typically compensate and produce enough saliva on their own.
Preventing Recurrence
Salivary stones can come back, especially in people with ongoing risk factors. Staying well hydrated is the single most effective preventive step. If you take medications that dry out your mouth, talk to your prescriber about alternatives or use saliva substitutes. Chewing sugar-free gum throughout the day keeps saliva flowing and prevents minerals from settling in the ducts. Avoiding tobacco also helps, since smoking irritates and narrows the ducts over time.