Swollen Tongue: What are the Causes?

Causes

Common tongue swelling causes are:

1. Allergic Reactions

Allergies, the most widespread tongue swelling causes, are triggered by a misdirected immune system. If you swallow or eat something your body sees as harmful—even if it's harmless to others—your immune system may react by causing inflammation, including swelling of the tongue. Certain foods like dairy, eggs, shellfish may lead to these reactions. The other possible triggers could be latex allergy, insect bites, or allergy to certain medications.

2. Injury

If your tongue gets injured due to accidental biting or piercing, you may develop tongue swelling. The tongue is full of sensitive muscles and blood vessels. Therefore, any injury to the tongue can be very painful and can cause swelling.

3. Infections

Infections are another common cause of tongue swelling. They can be viral, fungal, or bacterial. These harmful microorganisms often enter the tongue through small openings, such as cuts, sores, or piercings, and can infect the underlying tissues. When this happens, the tongue may become swollen, tender, and painful. You may even develop fever along with swelling. Cellulitis or strep throat, oral thrush, and an infection caused by the Epstein-Barr virus or the Herpes Simplex virus are some common triggers behind infectious tongue swelling.

4. Irritants

Some substances may act as irritants for your sensitive tongue, causing inflammation and swelling. The common tongue irritants could be mouthwashes, alcohol, tobacco, certain kinds of toothpaste, spicy foods, and additives such as mint or cinnamon. If you notice tongue swelling after exposure to any of these, it’s best to avoid them in the future to prevent further irritation.

5. Lack of Vitamins and Minerals

If your body does not get a steady supply of essential vitamins and minerals, you could have a swollen tongue. Deficiencies of folate, iron, and vitamin B12 are among the basic nutritional deficiencies that may cause tongue swelling or glossitis.

6. Health Conditions

Certain health conditions may trigger tongue swelling. Hypothyroidism, angioedema, down syndrome, amyloidosis, lupus, and tongue cancer are some of the leading tongue swelling causes. Let’s understand this in detail.

• Hypothyroidism

This condition slows down your metabolism and causes fluid retention, which can lead to generalised swelling throughout the body— including the tongue. A swollen, enlarged tongue is sometimes observed in untreated or advanced hypothyroidism.

• Angioedema

This is a rapid-onset swelling that often affects the face, lips, and tongue. It may occur due to allergic reactions, certain medications (like ACE inhibitors), or hereditary factors. In severe cases, angioedema can obstruct the airway and become a medical emergency.

• Down Syndrome

Individuals with Down syndrome often have a naturally larger tongue relative to their oral cavity, which may appear swollen. Additionally, low muscle tone and other anatomical differences can exaggerate this appearance, though it's not always due to inflammation.

• Amyloidosis

This rare condition involves the buildup of abnormal protein deposits (amyloid) in tissues and organs. When these deposits accumulate in the tongue, it can lead to persistent swelling, stiffness, and difficulty with speech and swallowing.

• Lupus

As an autoimmune disease, lupus can cause inflammation in various parts of the body, including the mucous membranes of the mouth. This can result in oral ulcers, discomfort, and swelling of the tongue and surrounding tissues.

• Tongue Cancer

Persistent or localised swelling of the tongue—especially if accompanied by lumps, ulcers, pain, or bleeding—may be a sign of oral cancer. It's essential to seek medical evaluation if swelling does not subside or worsens over time.

Other lesser-known causes of tongue swelling include:

• Certain dental procedures may lead to localised swelling and infections of the oral cavity, including the tongue.

• Obstructive sleep apnoea may trigger tongue enlargement, inflammation and unusual puffiness.

• Certain medications, like NSAIDs or ACE inhibitors, can cause your tongue to swell as one of the side effects.