What causes the face to swell on the left side?

There are several conditions that can cause the left side of the face to swell, including a blocked salivary gland, as stated by WebMD. Other causes include salivary gland disorders, according to Healthline.

Disorders that cause the left side, or one side, of the face to swell include:

• Sinusitis is a condition characterized by the sinuses and nasal passages swelling. Approximately 31 million people in the United States suffer from sinusitis each year.
• Cellulitis is a bacterial infection that occurs under the skin. The swollen area of the face may also feel hot to touch, indicating an underlying infection. It is also quite painful.
• People who have severe dental cavities or abscesses may experience facial swelling on the affected side. There is also accompanying pain from toothache.
• Head injuries that occur on the left side can produce swelling.
• Salivary gland disorders can produce swelling on the affected side. Certain viruses can produce swelling, such as the flu and mumps.
• When the salivary glands become infected, they begin to swell. There are three main types on each side, including the parotid and submandibular glands. They usually become infected because of bacterial infections.
• Actinomycosis is a bacterial infection that usually occurs in tropical regions of the world. One of the areas it affects is the mouth, which includes facial swelling.
• Burkitt's lymphoma is an aggressive form of non-Hodgkin's lymphoma. It is rare, but causes severe swelling.
• Both small cell lung cancer and non-small cell lung cancer cause facial swelling.
• Non-Hodgkin's lymphoma can cause facial swelling on the same side as the affected lymph nodes.