HCPCS Level II code S9504 represents a per diem administrative and professional pharmacy service for home infusion therapy of antibiotics, antivirals, or antifungals provided once every four hours. The code bundles care coordination, administrative oversight, professional pharmacy activities, and necessary supplies and equipment for home-based infusion, while the drugs themselves and nursing visits are billed separately. Nationally, this code matters because it standardizes billing for non-drug, non-nursing elements of home infusion programs that are expanding as outpatient and home-based care grows.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the clinical and billing scope of S9504, payer coverage patterns and benchmarking context where available, and guidance on common billing components tied to the per diem administrative service. The publication also outlines typical sites of service and service type to support correct claim placement and coding workflows. Data not available in the input is noted where applicable; the content focuses on the code definition, clinical context, and what to expect when S9504 is billed alongside separately coded drugs and nursing services.