Allergic contact dermatitis due to drugs in contact w skin

This code signifies an inflammatory skin reaction resulting from direct skin contact with a pharmaceutical agent. The dermatitis is an allergic response, not an irritant one, and manifests as erythema, vesicles, papules, and pruritus at the site of contact.

Apply this code when documentation clearly states allergic contact dermatitis caused by topical application of a drug, such as a medicated cream, ointment, or patch. Supporting documentation should specify the drug involved and confirm the allergic nature of the reaction.

• Differentiate from irritant contact dermatitis (L24.-) where the reaction is not immune-mediated.
• Ensure the drug was in contact with the skin; do not use for reactions to ingested medications.
• Review documentation for the specific drug to potentially use an additional external cause code (e.g., T49.- for adverse effects of topical agents).