Common causes of tongue swelling include allergic reactions, injury and vitamin deficiency, according to Healthline. Tongue inflammation rarely occurs by itself and is often associated with other health problems.
Allergic reactions to certain substances, such as toothpaste, mouthwash, dentures and retainers, often cause tongue swelling. Alcohol, spicy foods and tobacco products may also irritate the mouth and tongue. The tongue may swell after the inside of the mouth is burned or injured. Additionally, tongue inflammation may be a side effect of certain medications. Low levels of vitamin B-12 or iron may also cause tongue inflammation, states Healthline.
Sjogren's syndrome also may lead to tongue inflammation. The syndrome causes destruction of the saliva glands, which leads to dry mouth and tongue inflammation. Yeast infections and skin conditions such as oral lichen planus, syphilis and pemphigus may cause the tongue to swell, explains Healthline. Other conditions that cause tongue swelling include amyloidosis, cancer of the tongue, hypothyroidism, leukemia and tumor of the pituitary gland as well as Down syndrome and strep infection, according to MedlinePlus.
Tongue swelling that blocks the airway requires emergency medical attention. If swelling of the tongue makes it difficult to swallow, breathe or speak, individuals should contact their doctor. Additionally, individuals should contact their doctor if tongue swelling lasts more than 10 days. However, moderate swelling of the tongue usually goes away within a few days, explains Healthline.