What are the causes and treatments of lip swelling?

Causes and Treatment of Lip Swelling

Primary Causes of Lip Swelling

Lip swelling results from diverse etiologies including allergic reactions (angioedema, drug hypersensitivity), infections (bacterial, viral, fungal), inflammatory conditions (Stevens-Johnson syndrome/TEN, Kawasaki disease, cheilitis variants), hereditary angioedema, trauma, and structural lesions (cysts, tumors). 1, 2

Allergic and Immunologic Causes

• Angioedema represents IgE-mediated or bradykinin-mediated swelling affecting the lips, tongue, and face, potentially causing life-threatening airway obstruction 1
• Hereditary angioedema (HAE) with normal C1 inhibitor frequently manifests with facial and lip swelling, particularly in HAE-FXII, HAE-PLG, and HAE-ANGPT1 variants, with tongue swelling being especially prominent in HAE-PLG 1
• Drug hypersensitivity reactions including Stevens-Johnson syndrome/toxic epidermal necrolysis cause painful lip erythema progressing to hemorrhagic sloughing with dark adherent crusts 1
• Insect sting reactions can produce cutaneous manifestations including urticaria and angioedema affecting the lips and face 1

Infectious Causes

• Bacterial infections causing recurrent lymphangitis can lead to persistent lip swelling (elephantiasis nostras), requiring bacterial cultures and at least 14 days of appropriate antibiotics 3, 4, 5
• Viral infections including herpes simplex, Epstein-Barr virus (infectious mononucleosis), measles, and enterovirus can cause lip swelling and oral lesions 1, 4
• Candidal infections particularly angular cheilitis, frequently involve lip corners with erythema and fissuring 1, 3, 2

Inflammatory and Dermatologic Conditions

• Stevens-Johnson syndrome/toxic epidermal necrolysis presents with painful mucosal erythema, blistering, ulceration, and hemorrhagic crusting of the vermillion border 1
• Kawasaki disease manifests with erythema, lip cracking, fissuring, peeling, and bleeding as one of the principal diagnostic criteria 1
• Cheilitis variants include angular, contact (allergic/irritant), actinic, glandular, granulomatous, exfoliative, and plasma cell types, classified as reversible versus irreversible based on etiology 2
• Cheilitis granulomatosa presents with persistent lip swelling and epithelioid cell granulomas on histopathology, not responding to corticosteroids or antihistamines 5

Structural and Traumatic Causes

• Dentigerous cysts with mesiodens can cause slow-growing painless upper lip swelling, appearing as radiolucent areas on imaging 6, 7
• Trauma from displaced or dilacerated teeth can cause recurrent upper lip swelling 8
• Salivary tumors should be considered in the differential diagnosis of persistent lip swelling 6, 7

Treatment Approach

Immediate Management for Acute Lip Swelling

Apply white soft paraffin ointment to the lips immediately and then every 2 hours throughout the acute phase to provide barrier protection and maintain moisture. 1, 3, 4

• Clean the mouth daily with warm saline mouthwashes to reduce bacterial colonization 1, 3, 4
• Use benzydamine hydrochloride anti-inflammatory oral rinse or spray every 2-4 hours, particularly before eating, for pain control 1, 3, 4
• Apply viscous lidocaine 2% topically (15 mL per application) if pain is inadequately controlled with benzydamine 1, 4
• Avoid alcohol-containing mouthwashes as they exacerbate pain and delay healing 3, 4

Treatment Based on Specific Etiology

For Inflammatory Causes (SJS/TEN, Severe Cheilitis)

• Apply topical corticosteroids four times daily: betamethasone sodium phosphate 0.5 mg in 10 mL water as a 3-minute rinse-and-spit preparation 1, 9, 3
• For localized severe inflammation, apply clobetasol propionate 0.05% mixed in equal amounts with Orabase directly to affected areas daily 1, 9
• Consider systemic corticosteroids (prednisone 30-60 mg or 1 mg/kg for 1 week with tapering) for highly symptomatic or refractory cases 9, 3

For Infectious Causes

• Obtain bacterial cultures if infection is suspected and administer appropriate antibiotics for at least 14 days 3, 4
• Use antiseptic oral rinse twice daily: 0.2% chlorhexidine digluconate mouthwash (10 mL) or 1.5% hydrogen peroxide mouthwash 1, 3
• For candidal infections, treat with nystatin oral suspension 100,000 units four times daily for 1 week, or miconazole oral gel 5-10 mL held in the mouth after food four times daily for 1 week 1, 3, 4
• For angular cheilitis, use combination antifungal and corticosteroid therapy to address both Candida and inflammation 3

For Allergic/Angioedema

• Administer antihistamines and oral corticosteroids for large local reactions, though definitive proof of efficacy through controlled studies is lacking 1
• Prescribe injectable epinephrine for patients with history of systemic reactions or hereditary angioedema 1
• Consider venom immunotherapy for patients with recurrent insect sting-related angioedema and detectable venom-specific IgE 1

Supportive Care Measures

• Lubricate lips with sterile vaseline/white paraffin, lip balm, or lip cream, but avoid chronic use of petroleum-based products as they promote mucosal dehydration and increase secondary infection risk 1, 4
• Drink ample fluids to keep the mouth moist 1
• Use mucoprotectant mouthwash (e.g., Gelclair) three times daily to protect ulcerated mucosal surfaces 1, 9
• Maintain optimal nutritional support, with soft, moist, low-acidity foods if tolerated 1

Treatment for Refractory Cases

• Apply tacrolimus 0.1% ointment twice daily for 4 weeks for recalcitrant lesions 9
• Consider intralesional triamcinolone injections in conjunction with topical clobetasol for ulcers unresponsive to topical treatment 9

Critical Pitfalls to Avoid

• Never use alcohol-containing mouthwashes in acute lip inflammation as they cause additional pain and irritation 3, 4
• Do not chronically use petroleum-based products on lips as they promote mucosal cell dehydration and create occlusive environment leading to secondary infection risk 1, 4
• Do not prescribe antibiotics for large local reactions unless there is evidence of secondary infection, as swelling is caused by mediator release, not infection 1
• Avoid misdiagnosing bacterial adenitis when lymphangitis accompanies lip swelling 1
• Reevaluate diagnosis if no improvement occurs within 2 weeks of appropriate treatment 3

Special Populations

• Immunocompromised patients require more aggressive and prolonged therapy due to increased risk of secondary infections 3
• Elderly patients with frequent mouth ulcers and lip involvement may benefit from high-protein oral nutritional supplements 9
• Patients on targeted cancer therapies should use saline-containing mouthwashes instead of plain water due to increased microbial burden 1