What is the appropriate initial management for an adult patient with no known medical history presenting with acute lip swelling?

Initial Management of Acute Lip Swelling in Adults

The first priority is to immediately assess for anaphylaxis by looking for respiratory compromise (dyspnea, wheeze, stridor), hypotension, or multi-system involvement (skin, respiratory, gastrointestinal symptoms), and if present, administer intramuscular epinephrine 0.3-0.5 mg in the lateral thigh and activate emergency medical services. 1

Immediate Assessment Algorithm

Step 1: Rule Out Life-Threatening Anaphylaxis

Look specifically for these features that indicate anaphylaxis 1:

• Respiratory involvement: difficulty breathing, throat closing sensation, wheeze, stridor, or voice changes
• Cardiovascular signs: dizziness, syncope, hypotension, or pallor
• Multi-system involvement: lip swelling PLUS urticaria/flushing PLUS respiratory or gastrointestinal symptoms (vomiting, cramping)
• Recent exposure: foods (especially peanuts, tree nuts, shellfish), insect stings, or medications within minutes to hours 1

If any of these are present:

• Administer epinephrine autoinjector immediately into the lateral thigh if available 1
• Activate emergency medical services 1
• Consider repeat epinephrine dose after 5-10 minutes if no response and EMS delayed 1
• Delayed epinephrine is associated with increased mortality 1

Step 2: Assess Airway Patency

Examine for 2:

• Laryngeal involvement: change in voice, stridor, dysphagia, or dyspnea
• Oropharyngeal extension: tongue or uvular swelling
• If laryngeal edema is present or suspected, the patient requires intensive care monitoring and potential definitive airway management 2

Non-Anaphylactic Acute Lip Swelling Management

Initial Supportive Care (All Cases)

Once anaphylaxis is excluded, begin immediate symptomatic treatment 1, 3, 4:

• Apply white soft paraffin ointment to lips every 2 hours for barrier protection and moisturization 1, 3, 4
• Clean with warm saline mouthwashes daily to reduce bacterial colonization 1, 4
• Use benzydamine hydrochloride oral rinse/spray every 3 hours for anti-inflammatory effect and pain control 1, 3, 4
• Apply mucoprotectant mouthwash (e.g., Gelclair) three times daily if mucosal ulceration present 1, 4

Step 3: Identify Underlying Cause

Medication-induced angioedema 5:

• Review for ACE inhibitors (lisinopril, enalapril) - can occur at any time during treatment
• Discontinue offending medication immediately and consult prescribing physician 5
• African-American patients have higher risk 5

Infectious causes 6, 7:

• Impetigo: honey-colored crusting, pustular lesions, fever, induration 6
• Abscess: unilateral swelling, fluctuance, fever, severe pain 7
• Obtain bacterial cultures if infection suspected 3
• Initiate antiseptic oral rinse (0.2% chlorhexidine or 1.5% hydrogen peroxide) twice daily 1, 4
• Administer appropriate antibiotics for at least 14 days 3
• Abscess requires urgent surgical drainage 7

Hereditary angioedema 2:

• Spontaneous onset without clear trigger
• May have family history or recurrent episodes
• Does NOT respond to antihistamines or corticosteroids
• Requires C1 esterase inhibitor testing 2

Pain Management Escalation

If benzydamine inadequate 1, 4:

• Viscous lidocaine 2%, 15 mL per application as topical anesthetic 1, 4
• For severe discomfort: cocaine mouthwashes 2-5% three times daily 1

Critical Pitfalls to Avoid

• Never delay epinephrine if anaphylaxis is suspected - it is associated with increased mortality 1
• Never use alcohol-containing mouthwashes - they cause additional pain and irritation 3, 4
• Never assume isolated lip swelling is benign - always assess for airway involvement 2
• Never overlook medication history - ACE inhibitor angioedema can occur after years of stable use 5

Reassessment Timeline

• Immediate: If respiratory symptoms develop or worsen, activate EMS 1
• 24-48 hours: If no improvement or worsening despite treatment, consider infectious etiology requiring drainage or alternative diagnosis 6, 7
• 2 weeks: If persistent without improvement, reevaluate diagnosis and consider underlying systemic conditions (immunosuppression, nutritional deficiencies) 3, 4, 8