Summary & Overview
HCPCS S9331: Home Infusion Intermittent Chemotherapy, Administrative and Pharmacy Services
HCPCS Level II code S9331 covers per diem administrative and professional pharmacy services, care coordination, and necessary supplies and equipment for intermittent home chemotherapy infusions (less than 24 hours), with drugs and nursing visits billed separately. This code is important for defining non-drug, non-nursing components of home-based chemotherapy care and influences billing workflows, care coordination models, and payer coverage policies nationally.
Key national payers in typical analyses include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise explanation of the clinical and service context for S9331, how the code separates administrative and professional pharmacy services from drug and nursing charges, and which payers commonly cover or adjudicate these service lines. The publication outlines benchmark topics, potential policy considerations affecting home infusion reimbursement, and the operational implications for billing teams and home infusion providers.
This summary equips revenue leaders, clinical program managers, and policy analysts with a clear understanding of the code’s role in home chemotherapy delivery, expected site-of-service alignment, and the scope of services captured by the per diem code.
Billing Code Overview
HCPCS Level II code S9331 describes home infusion therapy, intermittent (less than twenty-four hours) chemotherapy infusion provided on a per diem basis for administrative services, professional pharmacy services, care coordination, and all necessary supplies and equipment. The code excludes the cost of drugs and nursing visits, which are billed separately.
Service Type: Home infusion therapy — intermittent chemotherapy (per diem administrative and professional services)
Typical Site of Service: Patient's home (home health/home infusion setting)
Clinical & Coding Specifications
Clinical Context
A 62-year-old woman with metastatic colorectal cancer receives intermittent home infusion chemotherapy coordinated by a specialty pharmacy. The patient has an indwelling central venous catheter and is medically stable with prior in-clinic chemotherapy tolerated without acute reaction. A physician orders a home infusion regimen delivered on nonconsecutive days over a 24-hour period or less; chemotherapy drug billing is submitted separately. The home infusion vendor provides administrative services, professional pharmacy services (including compounding, dispensing, and therapeutic monitoring), care coordination with the oncology clinic and home health nursing, and all necessary supplies and equipment for each per diem service day.
Workflow: the oncology practice sends the order to the specialty pharmacy; the pharmacy verifies regimen, performs compounding and labeling, arranges courier delivery to the patient’s home, schedules home health nurse visits for catheter access and infusion start/stop, documents patient education and adverse event monitoring, and bills the per diem administrative/service fee under S9331 while billing drugs and nursing visits separately.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | When billing physician professional interpretation or oversight associated with the infusion service separate from technical services. |