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B85ICD-10-CM

Chapter 1 · A00–B99 · Certain Infectious and Parasitic Diseases

Pediculosis and phthiriasis

B85 is the ICD10 code used for documenting Pediculosis and phthiriasis in clinical and billing records.

What B85 covers · when clinicians use it

ICD-10 code B85 identifies Pediculosis and phthiriasis in the U.S. ICD-10-CM clinical and billing record set. It sits within the Certain Infectious and Parasitic Diseases chapter (A00–B99), the section that groups related diagnoses so providers, payers, and public-health agencies report them consistently. Clinicians and medical coders apply B85 when an encounter's findings match the Pediculosis and phthiriasis description, attaching it to the patient record so downstream insurance claims, payer audits, quality reporting, and epidemiological surveillance all reference the same standardized diagnosis. The ICD-10-CM is maintained by the Centers for Medicare & Medicaid Services and the CDC's National Center for Health Statistics, with an updated official code set released each U.S. fiscal year — always verify B85 against the current CMS/CDC release and your payer's documentation guidance before final use. This page summarizes documentation context for B85 and is a coding reference, not clinical, diagnostic, or billing advice.

B85 refers to Pediculosis and phthiriasis, a category of parasitic infestations that affect the skin, hair, or body through the presence of lice, mites, fly larvae, or other organisms. These conditions can lead to intense itching, skin damage, and secondary infections. Proper ICD10 coding ensures accurate diagnosis, timely treatment, and supports public health tracking, especially in densely populated or vulnerable communities.

Symptoms

  • Itching – Persistent and intense, especially at night (e.g., in scabies)
  • Visible parasites – Lice or larvae may be seen on skin or hair
  • Red bumps or sores – From bites or burrowing of mites or insects
  • Secondary infections – Due to scratching and skin damage
  • Rash or scaling – Especially around infested areas
  • Inflammation – Swelling or localized irritation
  • Unpleasant odor – In advanced cases of skin infestation or myiasis

Diagnosis

Diagnosis of Pediculosis and phthiriasis is primarily clinical, based on physical examination and patient symptoms. Dermoscopy, skin scrapings, or examination under magnification may help identify parasites or their eggs. In the case of myiasis, imaging or surgical exploration may be required to assess larval invasion beneath the skin.

ICD10 Code Usage

ICD10 code B85 is used in clinical documentation, insurance billing, and public health surveillance. It allows for standardized identification and treatment of ectoparasitic infestations. Accurate coding ensures patients receive appropriate care and supports efforts to control infestations in schools, shelters, and long-term care settings.

Related Codes

FAQs

Q1: What is ICD10 code B85?
A: It refers to Pediculosis and phthiriasis, a parasitic skin or body infestation classified in the ICD10 system for medical documentation and billing.

Q2: Are these conditions contagious?
A: Yes, most are easily spread through close contact, shared clothing, or bedding.

Q3: How are these treated?
A: Treatments include topical insecticides, oral antiparasitics, hygiene measures, and in some cases, manual removal of larvae or parasites.

Q4: Who is at risk?
A: Children, the elderly, those in crowded living conditions, and people with limited access to hygiene are most at risk.

Q5: Can infestations cause complications?
A: Yes, prolonged infestations may lead to skin infections, inflammation, or even systemic symptoms if untreated.

Conclusion

ICD10 code B85 is essential for accurately documenting and managing Pediculosis and phthiriasis. It supports proper treatment, outbreak control, and healthcare planning, especially in at-risk populations. Consistent use of this code improves care outcomes and public health responses to parasitic infestations.

Source: ICD-10-CM (CMS / CDC NCHS official code set)

Last reviewed:

This page is a documentation reference for the ICD-10-CM code set and is not clinical, diagnostic, or billing advice. Always verify codes against the official ICD-10-CM source and your payer's guidelines.

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