What is the appropriate ICD‑10 code for swollen lips?

ICD-10 Code for Swollen Lips

The appropriate ICD-10-CM code for swollen lips is R13.0 (Cheilitis) or K13.0 (Diseases of lips), depending on whether the swelling is inflammatory or non-inflammatory in nature.

Primary Coding Options

For Inflammatory Lip Swelling (Cheilitis)

• K13.0 is the standard code for diseases of the lips, including various forms of cheilitis 1
• This code encompasses inflammatory conditions such as angular cheilitis, contact cheilitis, plasma cell cheilitis, exfoliative cheilitis, and cheilitis glandularis 1

For Non-Inflammatory Edema

• R68.89 (Other general symptoms and signs) can be used for non-specific lip swelling when the etiology is unclear 2
• T78.3XXA (Angioedema, initial encounter) should be used if the swelling is due to angioedema 3

Context-Specific Coding

For Trauma-Related Swelling

• S00.531A (Contusion of lip, initial encounter) for traumatic lip injury with swelling 4
• The 7th character "A" indicates initial encounter; use "D" for subsequent encounters 2

For Allergic Reactions

• T78.3XXA (Angioedema) is appropriate when lip swelling is part of an allergic response 3
• L50.9 (Urticaria, unspecified) if associated with hives and lip involvement 2

For Infection-Related Swelling

• K13.0 remains appropriate, but consider adding secondary codes for specific infectious agents if identified 5
• B37.0 (Candidal stomatitis) if fungal infection is confirmed 5

Laterality Considerations

• Right lip = 1, Left lip = 2, Bilateral = 3 in the appropriate digit position 2
• If no bilateral code exists and both lips are affected, assign separate codes for right and left 2
• Use unspecified codes only when laterality cannot be determined 2

Critical Coding Pitfalls to Avoid

• Never use placeholder codes without the required 7th character when the code category requires it 2
• Always use the most specific code available rather than defaulting to unspecified categories 2
• Document the underlying cause (trauma, infection, allergy, inflammatory) to justify the code selection 1, 6
• For Kawasaki disease with lip changes, use M30.3 (Mucocutaneous lymph node syndrome) as the primary code, not a lip-specific code 2

Documentation Requirements

• Specify whether swelling is unilateral or bilateral 2
• Note associated symptoms (erythema, cracking, pain, discharge) to support code selection 2, 5
• Document temporal relationship to potential triggers (medications, allergens, trauma) 3
• Record response to initial treatment to guide follow-up coding 5