Swollen lips

While associated signs and symptoms will differ based on the cause of swollen lips, most cases of lip swelling present similarly. Some clinical features of lip swelling include, but may not be limited to:

• Swollen lips (symmetrical or asymmetrical, unilateral or bilateral, mild, moderate or severe, acute or chronic, sudden or gradual)
• Blisters
• Chapped lips
• Change in lip colour
• Fatigue
• Fever and chills
• Headache
• Pain and tenderness
• Skin sores or pus-filled bumps
• Watery eyes or itchy eyes
• Runny nose
• Nasal congestion

If the following features are also present, the patient is likely to be experiencing a severe anaphylaxis reaction and needs emergency medical care:

• Sudden or severe swelling of lips
• Swollen tongue
• Bluish colouration of the lips or fingernails
• The sensation of constricting airways and difficulty breathing
• Respiratory or breathing problems, such as shortness of breath, laboured breathing, wheezing, not breathing and choking
• Noisy breathing
• Drooling saliva
• Fever with red and tender areas
• Generalised edema or swelling of the body
• Hives or urticaria rash
• Intense distress
• Itching in the throat or mouth

The causes for swollen lips can be multifactorial, sometimes resulting from diseases specifically affecting the lips and at other times as a result of systemic diseases. Common causes of swollen lips include, but may not be limited to:

• Trauma or injury to the lips and mouth: Hematomas, or collection of blood in soft tissues outside blood vessels, can form in the lips following an injury or contusion to them.
• Sleeping in awkward positions: This can also injure the lips and cause them to swell overnight.
• Infections: Different areas of infection can cause the lips to swell or appear swollen: 
  • Oral herpes or cold sores: Caused by herpes simplex virus type 1 (and sometimes by type 2), herpes is a disease that can not be cured. Oral blisters and swelling can appear at the time of physical or psychological stress as cold sores in patients who have been infected.
  • Cellulitis: Bacterial infection affecting the deeper layers of skin (dermis) and subcutaneous tissues can occur anywhere in the body, including in the lips. 
  • Cystic acne: Acne near the lips can cause the lips to appear swollen by extension. 
  • Gingivitis: Swelling and inflammation of the gums due to bacterial infections can cause the lips to appear swollen externally.
• Dental braces: Constant irritation of the inner surface of the lips by dental braces can cause bruises or minor swelling, which usually resolves on its own.
• Angioedema: Severe allergic reactions can cause vasoconstriction of blood vessels, causing them to narrow and the fluid within them to pool outside. Edema or fluid collection occurs throughout the body in such conditions but is more pronounced and noticeable in the eyes and the lips, as the skin in these areas is much thinner. Angioedema is a medical emergency and hospital care should be sought immediately.
• Oral allergy syndrome: A cluster of changes in the skin and mucous membranes of the mouth and throat following ingestion of a food allergen like certain fresh fruits, nuts and vegetables. Oral allergy syndrome can be associated with burning, itching and swelling of the lips, mouth and pharynx. Vomiting, diarrhea and gastrointestinal problems are common. Skin hives and allergic anaphylaxis are also possible in severe cases. Interestingly, the foods a person is prone to develop oral allergy syndrome from after ingestion are typically the ones that are pollinated by the same type of pollen. For example, if a person suffers from oral allergy syndrome after eating bananas, which are pollinated by ragweed pollen, there is also a small chance of allergic reaction upon eating other fruits and vegetables pollinated by ragweed pollen, including watermelon, cantaloupe, honeydew, zucchini and cucumber.
• Cheilitis: Inflammation of the lips is called cheilitis. Various different types of cheilitis can occur but a few are predominantly associated with lip swelling. A brief classification of different types of cheilitis is given below:
  • Cheilitis simplex: Dried chapped lips that occur commonly with dehydration and loss of moisture. 
  • Actinic cheilitis: Exposure to excessive sunlight can cause this.
  • Eczematous cheilitis: Atopic dermatitis or eczema affecting the skin of the lips can cause swollen lips. 
  • Infectious cheilitis: Lip infections are common with fungi like candida and bacteria like staphylococcus aureus and streptococcus pyogenes can cause lip swelling.
  • Cheilitis granulomatosa: Granulomas can form with certain types of inflammation that cause lumps to form in lips. Chronic lip swelling occurs with cheilitis granulomatosis associated with Melkersson Rosenthal Syndrome. 
  • Cheilitis glandularis: It is an inflammatory condition affecting the minor salivary glands. The lips, predominantly the lower lip, become swollen and everted. Mucopurulent discharge can be associated with it. It usually occurs due to poor hygiene in middle-aged men.
• Drug-related side effects: The lips can become swollen as an adverse reaction to certain medicines. Some medicines that can cause swollen lips include isotretinoin and other retinoids used for skin conditions. Penicillin allergies in susceptible individuals can also cause swollen lips.
• Excessive use of dermal lip fillers: Cosmetic beauty treatments by aesthetic doctors to enhance the fullness and shape of the lips is a common practice nowadays. However, sometimes, overzealous filling of dermal filler upon patient request can cause distortion of the lip proportion, shape and size.
• Melkersson Rosenthal Syndrome: A very rare neurological disorder that causes recurrent paralysis of facial muscles, swelling of the face and lips, and furrows and folds to form in the tongue. The lip swelling is confined to the upper lip and is known as Cheilitis granulomatosis. While at first upper lip swelling occurs episodically, it can later persist and become permanent.
• Lip carcinoma: Another rare cause of lip swelling is oral carcinoma of the lips. Tobacco chewing, smoking cigarettes, drinking alcohol and excessive exposure to the sun are risk factors for developing lip cancer and other types of oral cancers.

The doctor will begin by taking a thorough medical history from the patient, laying special focus on preexisting health conditions and any long-term or short-term medications being taken. A note will also be made about the onset of the lip swelling noticed by the patient. Following this, a comprehensive clinical examination of the patient will be conducted. Systemic examination of the nervous system is important to potentially uncover any underlying neurological causes for the appearance of swollen lips. Oral examination with tongue depressors, speculums and some specialised mirrors is also warranted. In some cases, a reference may be made to a dentist for a dental examination if required. After examining the patient, some laboratory investigations may be requested; however, swollen lips largely remain a clinical diagnosis.

Some investigations may be sought if malignancy is suspected.

• Biopsy: A small part of the suspicious tissue from the lip swelling will be removed by the doctor. A pathologist will assess it under a microscope to diagnose cancer.
• Radiological imaging: CT scan can help stage the cancer if present and detect its spread in the body. A PET scan can also be used to pick up metastasis.

The treatment of swollen lips will be guided by the underlying disease or disorder that caused it. Some common principles for managing swelling of the lips are:

• Conservative management: Ice packs can help reduce the swelling of lips, especially in instances following trauma or injury.
• Medical management:
  • NSAIDs or over the counter painkillers can help reduce inflammation, pain and swelling of the lips.
  • Corticosteroids may be helpful in reducing lip swelling due to inflammatory diseases as well.
  • Antihistamines and anti-allergic medicines: Conditions like food pollen allergy or other allergic causes of swollen lips respond well to antihistamine medicines.
  • Dissolving lip dermal fillers with hyaluronidase injections: Hyaluronic-acid-based fillers are the ones that are most commonly used today for facial enhancements by doctors. If these fillers do not produce the desired cosmetic outcome, the patient may request to dissolve these fillers. Hyaluronidase is injected by the specialist into the lips and it slowly dissolves the hyaluronic acid filler.
• Surgical management: Surgery is not needed in most cases of swollen lips unless a malignant or premalignant condition is diagnosed.
  • A biopsy followed by surgical removal of part of the lip and surrounding tissue margin in case of diagnosed lip cancer. Radiation therapy is used after surgical resection of lip cancer.
  • Verimillectomy: Cheilitis glandularis is a premalignant condition in which part of the lip may need to be shaved to prevent conversion to cancer.

Untreated or undiagnosed swollen lips can have potentially serious complications like:

• Lip cancer: Some conditions that cause lip swelling are known to be precursors for cancer. In some cases, prophylactic treatment is necessary to prevent cancer from occurring.
• Anaphylaxis: Severe allergic reactions can occur due to unrecognised allergies.
• Respiratory arrest: If angioedema is not recognised and managed on time, the patient's airways may collapse and this may even prove to be fatal.
• Sepsis: Bacteria can travel from gum and lip infection into the bloodstream and cause sepsis and septic shock.
• Endocarditis: Bacterial gingivitis is associated with bacterial endocarditis by transmigration of bacteria.
• Permanent lip swelling or disfigurement.

Although all causes of lip swelling are not avoidable, some of the following precautions can be taken:

• Avoid chewing tobacco
• Avoid smoking cigarettes
• Avoid alcohol consumption
• Stay protected and use appropriate SPF-based sunscreens while out in the sun
• Reduce sun overexposure
• Avoid tanning practices
• Maintain good oral hygiene
• Practice safe sex to prevent herpes infections
• Recognise allergies and prevent exposure to known allergens