What is the best course of treatment for a swollen lip that has lasted for 12 hours?

Management of Lip Swelling Present for 12 Hours

The most critical first step is to determine if this represents anaphylaxis or angioedema requiring immediate epinephrine administration, versus a localized inflammatory or infectious process that can be managed with topical and oral therapies. 1, 2

Immediate Assessment and Emergency Treatment

If the patient exhibits any signs of anaphylaxis—including difficulty breathing, throat tightness, generalized urticaria, or systemic symptoms—administer intramuscular epinephrine 0.3-0.5 mg immediately in the anterolateral thigh and activate emergency medical services. 1, 2

• Anaphylaxis signs include lip and facial swelling combined with difficulty breathing, throat closing sensation, rash, vomiting, dizziness, or altered consciousness 1
• Epinephrine is the definitive first-line treatment and should never be delayed if anaphylaxis is suspected 1
• Observe for at least 2-4 hours after symptom resolution due to risk of biphasic reactions 1

For Isolated Lip Swelling Without Systemic Symptoms

First-Line Topical Management

Apply white soft paraffin ointment to the lips every 2 hours for protection and moisture barrier. 3, 4

Apply topical corticosteroids four times daily to reduce inflammation—specifically clobetasol propionate 0.05% mixed in equal amounts with Orabase for localized application. 3, 4

• Benzydamine hydrochloride oral rinse or spray every 2-4 hours provides pain relief, particularly before eating 3, 5, 4
• Clean the area with warm saline mouthwashes daily to reduce bacterial colonization 3, 5, 4

Systemic Anti-inflammatory Therapy

For significant swelling at 12 hours, consider oral corticosteroids: prednisolone 30-35 mg daily for 3-5 days. 1, 5

• NSAIDs (ibuprofen 600 mg three times daily) can be added for additional anti-inflammatory effect and pain control 1
• Antihistamines provide minimal benefit for established swelling but may prevent progression if allergic etiology 6

Rule Out Infectious Causes

Examine carefully for signs of bacterial infection (MRSA lip abscess can mimic angioedema): warmth, fluctuance, purulent drainage, or surrounding cellulitis. 7

• If infection is suspected, obtain bacterial cultures and initiate antibiotics covering MRSA (e.g., trimethoprim-sulfamethoxazole or clindamycin) for at least 14 days 1, 4
• Consider incision and drainage if abscess is present 1
• If candidal infection suspected (angular cheilitis pattern), treat with nystatin oral suspension 100,000 units four times daily or miconazole oral gel for 1 week 3, 5, 4

Second-Line Treatments for Persistent Swelling

If swelling persists beyond 48-72 hours despite initial therapy, consider tacrolimus 0.1% ointment applied twice daily for 4 weeks. 3, 5

• Intralesional triamcinolone injections may be considered for refractory cases 3, 5

Critical Pitfalls to Avoid

Do not dismiss isolated lip swelling as simple angioedema without considering MRSA infection, which can be life-threatening if misdiagnosed. 7

• Some forms of angioedema (hereditary or ACE-inhibitor induced) do not respond to epinephrine, antihistamines, or corticosteroids and require specialized management 6
• Avoid alcohol-containing mouthwashes which cause additional irritation 4
• Evaluate treatment response within 2 weeks; if no improvement, reevaluate diagnosis 4

Follow-up Instructions

• Return immediately if breathing difficulty, throat tightness, or systemic symptoms develop 1
• Reassess within 24-48 hours to ensure improvement and rule out progression 1
• If recurrent episodes occur, investigate underlying causes including drug reactions, food allergies, or hereditary angioedema 1, 6