Medicare is a federal program providing health insurance for people aged 65 or older, younger people with certain disabilities, and individuals with End-Stage Renal Disease. Home Infusion Therapy (HIT) involves delivering medications intravenously or subcutaneously to a patient in their home rather than in an institutional setting. While Medicare covers home infusion, the benefit is complex because different components of the therapy are covered under various parts of the program. Determining whether Part B or Part D applies is the first step in understanding coverage for this specialized care.
Defining Home Infusion Therapy and Its Components
Home Infusion Therapy administers prescription drugs and biologicals to treat acute and chronic conditions, such as infections, cancer, and immune deficiencies. This complex medical service requires the coordination of three interdependent components: the actual medication (the drug or biological substance); professional services (skilled nursing care, pharmacist services for drug compounding, patient training, and continuous monitoring); and necessary supplies and equipment (infusion pump, specialized tubing, catheters, IV poles, and sterile dressing kits). All three elements must be covered for the therapy to be feasible in a home setting.
The Specific Medicare Coverage for Infusion Services
Medicare covers the professional services and equipment component of home infusion through the dedicated Home Infusion Therapy (HIT) benefit under Medicare Part B. Established by the 21st Century Cures Act, this benefit became effective on January 1, 2021, covering services associated with administering certain infusion drugs that require a Durable Medical Equipment (DME) pump for delivery.
The Part B HIT benefit provides professional support necessary for safe and effective therapy in the home. This includes skilled nursing services for initial patient assessment, training the patient or caregiver on pump use, and catheter care. It also covers the pharmacist’s clinical monitoring, patient education, and remote monitoring of the infusion process.
The legal framework is rooted in the Social Security Act, section 1861(iii)(2), which defines HIT services to include professional services, training, education, and monitoring provided by a qualified, accredited supplier. The supplier is paid a bundled rate for these services on a per-day basis when the drug is administered. The infusion pump and associated supplies are covered separately under the Part B DME benefit.
How Medications for Home Infusion Are Covered
Coverage for the drug or biological administered during home infusion is determined separately from professional services, depending on the drug type and administration method. Part B covers a limited number of parenteral drugs and biologicals that must be administered via a DME pump, such as certain chemotherapy agents and immunosuppressants. To qualify under Part B, the drug must be administered intravenously or subcutaneously for a minimum of 15 minutes using an external pump.
Part B also covers drugs furnished “incident to” a physician’s service, meaning the drug is administered by a healthcare professional in the home as part of the treatment plan. However, the majority of home infusion drugs, including most intravenous anti-infectives and certain nutritional therapies, are covered under Medicare Part D.
Part D is the outpatient prescription drug benefit, covering only the cost of the medication itself, not the associated supplies, equipment, or professional services. If a home infusion drug is covered by Part D, the beneficiary is responsible for the separate costs of nursing services and supplies, unless they qualify for the Part B HIT services benefit. This distinction can create financial gaps for patients, as the Part B HIT benefit applies only to the limited list of drugs covered under Part B.
Patient Financial Responsibility and Eligibility Rules
Beneficiaries must meet specific eligibility requirements for Medicare coverage. The therapy must be medically necessary, prescribed by a licensed physician as part of a detailed plan of care. Services must be provided by a qualified home infusion therapy supplier that is accredited and enrolled with Medicare.
For services covered under Medicare Part B, including HIT professional services and Part B-covered drugs, the beneficiary is responsible for cost-sharing. After the annual Part B deductible is met, the patient pays a 20% coinsurance of the Medicare-approved amount for the services, supplies, and Part B drugs. Unlike the Medicare Home Health benefit, the patient is not required to be “homebound” to receive Part B HIT services.
The 20% coinsurance can accumulate quickly, especially for long-term or high-cost therapies. Patients with a Medicare Advantage plan (Part C) or supplemental insurance, such as Medigap, may have a different financial burden, as these plans often cover some or all of the coinsurance and deductible.