2026 ICD-10-CM Diagnosis Code B02.21Postherpetic geniculate ganglionitis

ICD-10-CM Codes›A00–B99›B00-B09›B02

ICD-10-CM B02.21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B02.21 is a billable ICD-10-CM diagnosis code for postherpetic geniculate ganglionitis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 974 through 976. Coders also document this condition as acute geniculate ganglionitis caused by Human herpesvirus 3. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nerve and nerve root disorders and Viral infection.

Code Identity

ICD-10-CM Code
B02.21
Billable Status
Yes — Valid for Submission
Code Describes
Postherpetic geniculate ganglionitis
Short Description
Postherpetic geniculate ganglionitis
Same as the full description in the CMS dataset.
Parent Code
B02.2
Zoster with other nervous system involvement

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB00-B09Viral infections characterized by skin and mucous membrane lesions
CategoryB02Zoster [herpes zoster]
This CodeB02.21Postherpetic geniculate ganglionitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute geniculate ganglionitis caused by Human herpesvirus 3
  • Facial neuralgia
  • Geniculate ganglionitis
  • Herpes zoster auricularis
  • Herpes zoster dermatitis
  • Nervus intermedius neuralgia

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Disease, diseased
      • Hunt's (herpetic geniculate ganglionitis) (neuralgia)
    • Ganglionitis
      • gasserian (postherpetic) (postzoster)
    • Ganglionitis
      • geniculate
        • postherpetic, postzoster
    • Ganglionitis
      • herpes zoster
    • Ganglionitis
      • postherpetic geniculate
    • Herpes, herpesvirus, herpetic
      • geniculate ganglionitis
    • Herpes, herpesvirus, herpetic
      • zoster
        • auricularis
    • Herpes, herpesvirus, herpetic
      • zoster
        • geniculate ganglionitis
    • Herpes, herpesvirus, herpetic
      • zoster
        • oticus
    • Hunt's
      • disease or syndrome (herpetic geniculate ganglionitis)
    • Hunt's
      • neuralgia
    • Neuralgia, neuralgic(acute)
      • Hunt's
    • Neuritis(rheumatoid)
      • geniculate ganglion
        • due to herpes (zoster)
    • Ramsay-Hunt disease or syndrome
    • Syndrome
      • Hunt's (herpetic geniculate ganglionitis) (neuralgia)

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR NVS017
Nerve and nerve root disorders
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INF008
Viral infection
Default principal diagnosis: inpatient No · outpatient No

Clinical InformationClinical

  • Facial Neuralgia

    neuralgic syndromes which feature chronic or recurrent facial pain as the primary manifestation of disease. disorders of the trigeminal and facial nerves are frequently associated with these conditions.

  • Facial Pain

    pain in the facial region including orofacial pain and craniofacial pain. associated conditions include local inflammatory and neoplastic disorders and neuralgic syndromes involving the trigeminal, facial, and glossopharyngeal nerves. conditions which feature recurrent or persistent facial pain as the primary manifestation of disease are referred to as facial pain syndromes.

  • Herpes Zoster Dermatitis

    painful, localized rash caused by reactivation of latent varicella zoster virus residing in nerve cell bodies, with resulting infection of the skin in the region supplied by the affected nerve.

  • Herpes Zoster Dermatitis of Eyelid

    a form of herpes zoster infection characterized by dermatitis of the skin of the eyelid due to reactivation of latent virus associated with the ophthalmic branch of the trigeminal nerve.

Patient EducationClinical

Shingles

Shingles (herpes zoster) is an infection that causes a painful rash. It is caused by the varicella-zoster virus (VZV). This is the same virus that causes chickenpox. After you have chickenpox, the virus stays in your body. It may not cause problems for many years. But as you get older, the virus may become active again and cause shingles.

The full article covers:

  • What is shingles?
  • Is shingles contagious?
  • Who is at risk for shingles?
  • What are the symptoms of shingles?
  • What other problems can shingles cause?
  • How is shingles diagnosed?
  • What are the treatments for shingles?
  • Can shingles be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert B02.21 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
053.11 Geniculate herpes zoster
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About B02.21Overview

Is B02.21 (Zoster with other nervous system involvement) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report postherpetic geniculate ganglionitis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does B02.21 group to?

When postherpetic geniculate ganglionitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 974, 975, 976, with relative weights from 0.8945 to 2.8860 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of B02.21?

Under the General Equivalence Mappings, postherpetic geniculate ganglionitis converts to ICD-9-CM 053.11 (geniculate herpes zoster). The mapping is a direct match.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.