2026 ICD-10-CM Diagnosis Code L56.1Drug photoallergic response

ICD-10-CM Codes›L00–L99›L55-L59›L56

ICD-10-CM L56.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L56.1 is a billable ICD-10-CM diagnosis code for drug photoallergic response. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607. Coders also document this condition as drug-induced persistent light reaction. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Allergic reactions and Other specified and unspecified skin disorders.

Code Identity

ICD-10-CM Code
L56.1
Billable Status
Yes — Valid for Submission
Code Describes
Drug photoallergic response
Short Description
Drug photoallergic response
Same as the full description in the CMS dataset.
Parent Code
L56
Other acute skin changes due to ultraviolet radiation

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL55-L59Radiation-related disorders of the skin and subcutaneous tissue
CategoryL56Other acute skin changes due to ultraviolet radiation
This CodeL56.1Drug photoallergic response

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Drug-induced persistent light reaction
  • Photosensitivity caused by drug

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Use Additional Code

  • code for adverse effect, if applicable, to identify drug T36 T50

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.

    • Reaction
      • drug NEC
        • photoallergic
    • Response(drug)
      • photoallergic

Clinical ClassificationClinical

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

CCSR INJ031
Allergic reactions
Default principal diagnosis: inpatient No · outpatient No
CCSR SKN007
Other specified and unspecified skin disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Drug Reactions

Most of the time, medicines make our lives better. They reduce aches and pains, fight infections, and control problems such as high blood pressure or diabetes. But medicines can also cause unwanted reactions, such as drug interactions, side effects, and allergies.

The full article covers:

  • What is a drug interaction?
  • What are side effects?
  • What are drug allergies?
  • How can I stay safe when taking medicines?

Read the full article at MedlinePlus

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

Convert L56.1 to ICD-9-CMHistory

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

ICD-9-CM
692.72 Act drmtitis solar rdiat
Approximate The match is approximate rather than exact.

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 L56.1Overview

Is L56.1 (Other acute skin changes due to ultraviolet radiation) a billable code?

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

What MS-DRG does L56.1 group to?

When drug photoallergic response is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, with relative weights from 0.9064 to 1.5132 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of L56.1?

Under the General Equivalence Mappings, drug photoallergic response converts to ICD-9-CM 692.72 (act drmtitis solar rdiat). The mapping is approximate, so confirm the match fits the documentation.

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.