Drug-induced pemphigus

This code represents a rare autoimmune blistering skin disorder characterized by the development of vesicles and bullae on the skin and mucous membranes, specifically caused by an adverse reaction to a medication. The drug triggers an immune response that targets desmogleins, proteins responsible for cell adhesion within the epidermis.

Apply this code when documentation clearly indicates pemphigus as a direct consequence of drug exposure. This typically involves a temporal relationship between drug initiation and symptom onset, and often resolution or improvement upon drug withdrawal. Supporting documentation should identify the causative drug.

• Always sequence this code first when it is the primary reason for the encounter, followed by codes for the specific drug causing the adverse effect (T36-T50 with 5th or 6th character indicating adverse effect).
• Distinguish from other forms of pemphigus (e.g., L10.0 for Pemphigus vulgaris) where a drug is not the causative agent.
• Ensure the medical record explicitly states the drug as the etiology for the pemphigus, not merely a co-occurring condition.