Salivary glands are the glands located in and around the mouth and throat. The major salivary glands are the parotid, submandibular and sublingual glands. The function of these glands is to secrete saliva into the mouth in order to keep the mouth moist, lubricate and bind food, begin the digestion process and maintain oral hygiene. There are other, minor salivary glands located in the lips, inner cheek and linings of the mouth and throat.

The parotid is located near the upper teeth, and it produces a watery secretion through salivary ducts which drain the saliva. The submandibular is located under the tongue and produces a part transparent, part mucous secretion. The floor of the mouth contains ducts through which the sublingual gland secretes a mucous secretion.

The basic units of salivary glands are cell clusters called acini. These cells secrete water, electrolytes, mucus and enzymes, which flow into collecting ducts where the composition of the fluids change and are either reabsorbed or secreted. Saliva secretion is regulated by the autonomic nervous system, and salivation increases with the smell, thought or presence of food, as well as with the presence or thought of a foreign substance in the mouth. The salivary glands swell during eating and subside afterward.

Some problems that affect these glands include obstruction, infection, tumors and enlarged glands. Stones can form in the parotid or submandibular gland, causing a blocked salivary gland, which prohibits saliva from exiting the ducts. This leads to salivary gland swelling and pain or infection. One type of infection is mumps, during which the parotid gland swells. Too much bacteria in the mouth can lead to an infected salivary gland, and autoimmune diseases such as HIV cause inflammation of the salivary glands when the immune system attacks them.

A tumor in this area causes the enlargement of typically one salivary gland and a growth in the parotid, submandibular, palate, mouth floor, cheeks or lips. These tumors can be benign or malignant, and the latter can cause the loss of movement of part of the face. Enlarged salivary glands can result from diseases such as diabetes or arthritis.

Salivary gland disease should be treated differently according to each problem. Increased fluids can help because dehydration can put a person at risk for salivary gland disease. Antibiotics are also effective for mild problems, but sometimes surgery is needed to open a blocked salivary gland or to remove a mass within the gland.