What does this mean?
Under your jaw there is a large salivary gland on each side. What these glands produce runs through a fine duct that opens under your tongue. When you start eating, production rises within a few seconds. If there is a narrowing or a blockage anywhere along the duct, the saliva cannot get out; it builds up inside the gland and the gland swells enough to be seen. Once the meal is over production slows, the saliva that has built up seeps out slowly and the swelling goes down.
What sets this symptom apart is its timing. The swelling starts in the first few minutes of a meal, is at its most obvious at the table and most often gets smaller within half an hour to a few hours. The strongest trigger is sour tastes; a lemon, a pickle or a salad with vinegar on it can set the swelling off on its own. A swollen lymph node in the neck does not behave like this; that swelling stays the same size for days and does not come and go with meals. A blockage is also almost always on one side only.
When the same gland blocks a few times over, the wall of the duct can thicken and emptying becomes a little harder each time. In time the swelling starts not to settle completely after a meal. A swelling that becomes constant, skin over it that turns red, or a salty, unpleasant taste in your mouth suggests that inflammation has been added to the picture. A blockage is not always caused by a stone; a narrowed duct and, less often, causes arising in the gland itself can give the same picture.
Behind a swelling that comes and goes with meals there is most often a mechanical reason blocking the flow of saliva. The headings below are not ranked by frequency; they are the possibilities that the examination and the scans set out to tell apart.
Likely causes
What helps at home?
- Drink more water when the swelling starts; being short of fluid thickens the saliva and makes it even harder for it to pass along the duct.
- Do not squeeze the gland hard from the outside, and do not try to open the mouth of the duct with a needle or a toothpick; the wall of the duct is easily injured and can end up narrower as it heals.
- Note down which side it is on, which meal it started with and how many hours it took to settle; the gland will most often have gone down by the time you are examined, so that record stands in for what cannot be seen on the day.
- Do not start leftover antibiotics on your own; a mechanical blockage is not opened by an antibiotic, and if a picture with a high temperature does develop, the starting point will already have been muddied.
- If the swelling is still not going down hours after the meal and is still there the next day
- If the skin over the swelling has turned red or hot, or you have a high temperature
- If pus or a salty, foul-smelling fluid is coming into your mouth
- If you are having difficulty opening your mouth, swallowing or breathing
- If the floor of your mouth is swelling up and pushing your tongue upwards, or your voice has changed
Frequently asked questions
- The swelling went down on its own, do I still need to be seen?
- The swelling going down shows that the blockage has cleared for the moment; it does not show that the reason for it has gone. If the same gland blocks over and over, the duct narrows in time and the attacks come closer together. At the assessment the mouth of the duct is looked at, the flow is watched and, if needed, a scan is requested. An examination carried out while there is no swelling still gives useful information, so there is no need to put it off.
- Can a salivary stone come out on its own?
- Some of the small stones sitting near the mouth of the duct can work their way out in time. With larger stones, or ones sitting further back towards the gland, that is not expected and a procedure is needed to remove them. There is no way of telling where a stone is or how big it is by feel; the decision is made after a scan.
- Who should I see about this?
- A dentist can see the mouth of the duct from inside the mouth, judge whether there is any flow and tell whether the swelling is coming from a tooth or from the gland. Assessing the gland as a whole, and any scans, belong with an ear, nose and throat specialist. For stones close to the mouth of the duct, the procedure can be carried out by oral and maxillofacial surgery. If there is a high temperature, spreading swelling or difficulty swallowing, you need to be seen as an emergency without waiting.
This content is for general information and does not replace an in-person examination. Symptoms overlap between conditions, and a diagnosis can only be made clinically.