B00.4
Billable

Herpesviral encephalitis

Billable / Specific Code

What is Herpesviral encephalitis?

ICD-10-CM B00.4 is the diagnosis code for Herpesviral encephalitis. This code falls under the section "Viral infections characterized by skin and mucous membrane lesions" within Chapter 1 — Certain infectious and parasitic diseases (A00-B99). It is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.

💡 Inclusions
⛔ Excludes1

Coding Guidelines for B00.4

✅ This Code Includes

  • Herpesviral meningoencephalitis
  • Simian B disease

⛔ Type 1 Excludes (Never code together)

The following conditions should never be coded at the same time as B00.4. They are mutually exclusive:

  • herpesviral encephalitis due to herpesvirus 6 and 7 (B10.01, B10.09)
  • non-simplex herpesviral encephalitis (B10.0-)

ICD-10-CM Code Hierarchy

Understanding where B00.4 sits in the ICD-10-CM classification helps ensure proper coding:

Related Codes

Frequently Asked Questions

Is B00.4 a billable ICD-10-CM code?

Yes, B00.4 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.

What does B00.4 mean?

B00.4 is the ICD-10-CM diagnosis code for "Herpesviral encephalitis". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.

What is the parent code of B00.4?

The parent code of B00.4 is B00 ("Herpesviral [herpes simplex] infections"). B00.4 provides a more specific classification within this category.

What section is B00.4 in?

B00.4 is located in Section B00-B09 — "Viral infections characterized by skin and mucous membrane lesions" within Chapter 1 of the ICD-10-CM Tabular List.

When should I use B00.4?

Use B00.4 when the patients documented diagnosis matches "Herpesviral encephalitis" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.

People Also Ask

What is the ICD-10 code for Herpesviral encephalitis?

The ICD-10-CM code for Herpesviral encephalitis is B00.4.

Can B00.4 be used for primary diagnosis?

Yes, B00.4 can be used as a primary diagnosis code since it is billable and specific.

What chapter is B00.4 in?

B00.4 is in Chapter 1 of the ICD-10-CM Tabular List.

What conditions are excluded from B00.4?

Type 1 Excludes for B00.4 include: herpesviral encephalitis due to herpesvirus 6 and 7 (B10.01, B10.09); non-simplex herpesviral encephalitis (B10.0-).

Is B00.4 valid for 2026?

Yes, B00.4 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.

See Also

← PreviousB00.3Herpesviral meningitisNext →B00.5Herpesviral ocular disease
Code Details
B00.4
Herpesviral encephalitis
Billable / Specific Code
1 — Certain infectious and parasitic diseases (A00-B99)
B00-B09 — Viral infections characterized by skin and mucous membrane lesions
2026 ICD-10-CM