ICD-10-CM 2027
ICD-10 code for photoallergic response
From the official ICD-10-CM alphabetic index entry “Response (drug) › photoallergic”. Page updated September 29, 2026.
About coding photoallergic response
The ICD-10-CM code for photoallergic response is L56.1 (Drug photoallergic response).
Within L56 (other acute skin changes due to ultraviolet radiation), L56.1 is specifically for drug photoallergic response. Related codes cover drug phototoxic response (L56.0), Photocontact dermatitis [berloque dermatitis] (L56.2), solar urticaria (L56.3), Polymorphous light eruption (L56.4), disseminated superficial actinic porokeratosis (DSAP) (L56.5), other specified acute skin changes due to ultraviolet radiation (L56.8) and acute skin change due to ultraviolet radiation, unspecified (L56.9).
Use an additional code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5). Use an additional code to identify the source of the ultraviolet radiation (W89, X32).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Common questions about photoallergic response ICD-10 codes
What is the ICD-10 code for photoallergic response?
- L56.1 — Drug photoallergic response.
Is L56.1 billable?
- Yes. L56.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can L56.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict L56.1 as a principal diagnosis.
Is L56.1 a CC or MCC?
- No. L56.1 is neither a CC nor an MCC under MS-DRG v44.0.