ICD-10 Code B85.3 – Phthiriasis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B85.3 – Phthiriasis
What it is
B85.3 identifies infestation with lice, including pubic lice. Use it when the record documents phthiriasis or pediculosis due to lice.
Clinical signs
Typical findings include itching and visible lice or nits on affected hair-bearing skin. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents phthiriasis, lice infestation, or pubic lice affecting the patient. It is appropriate when the diagnosis is confirmed clinically or recorded as the reason for evaluation. If the note is unclear, check documentation.
Do not use for
Do not use B85.3 for nonspecific itching without documented lice infestation. Do not assign it when the chart describes another parasitic condition or only exposure without active infestation.
Coding tip
Code only when lice infestation is explicitly documented; otherwise, check documentation for a more specific diagnosis.