HCPCS code J1325 – Epoprostenol injection

Key takeaways

HCPCS Code J1325 bills epoprostenol injection (Flolan, Veletri and generic epoprostenol), a prostacyclin vasodilator infused continuously for pulmonary arterial hypertension.

One billing unit is 0.5 mg, so a 0.5 mg vial is 1 unit and a 1.5 mg vial is 3 units.

Medicare covers home epoprostenol under the external infusion pump policy, which requires pump K0455 and the KX modifier on pump, drug and supply lines.

Report the 11-digit NDC of the vial used, and add JW for discarded drug or JZ when none was discarded.

Pabau’s claims management software sends CMS-1500 claims through the Claim.MD clearinghouse and posts remittances against the patient record.

What HCPCS code J1325 covers

HCPCS code J1325 is the Level II code for “Injection, epoprostenol, 0.5 mg.” It bills the drug epoprostenol, sold as Flolan, Veletri and generic epoprostenol for injection. Each billing unit is 0.5 mg. The code appears in the CMS HCPCS quarterly file, and it is still active in the October 2026 release.

Epoprostenol is a prostacyclin vasodilator. The FDA label for Flolan indicates it for pulmonary arterial hypertension (PAH, WHO Group 1) to improve exercise capacity. Veletri carries the same indication.

J1325 does not describe epinephrine or adrenaline in any form. Epinephrine injection has its own code, HCPCS J0169 (Adrenalin brand) or J0165 (generic), billed per 0.1 mg.

CMS deleted the older epinephrine code, J0171, effective July 1, 2025. Epinephrine and epoprostenol sit close together in an alphabetical drug list, which is how claims for one end up under the other.

Clinical context: How epoprostenol is given

Epoprostenol is never given as a quick injection. The label calls for a continuous infusion through a central venous catheter, driven by an ambulatory pump the patient wears. A temporary peripheral line is allowed only until central access is in place, and bolus doses are ruled out.

That delivery method shapes the whole billing picture. The drug runs around the clock for months or years, and the patient mixes fresh cassettes at home. So most J1325 claims describe drug supplied for home use, not a dose a clinician pushed in the office.

• Starting dose: 2 ng/kg/min, raised in steps of 1 to 2 ng/kg/min at intervals of at least 15 minutes
• Starting setting: a site with the staff and equipment for physiologic monitoring and emergency care, usually a hospital
• Pump: small and light, adjustable in 2 ng/kg/min steps, with occlusion, end-of-infusion and low-battery alarms
• Backup: the patient keeps a spare pump and infusion sets, because a stopped infusion can cause rebound pulmonary hypertension

The products also differ at the mixing stage. Flolan is reconstituted only with its own pH 12 sterile diluent. Veletri and the generics are reconstituted with sterile water or 0.9% sodium chloride. That difference shows up on the claim, because the Flolan diluent has its own supply code, S0155.

How to calculate J1325 billing units

Bill one unit of J1325 for every 0.5 mg of epoprostenol. Divide the milligrams by 0.5 to get the units. The CMS NDC-to-HCPCS crosswalk confirms the vial math for every listed product. Each 0.5 mg vial is 1 billing unit, and each 1.5 mg vial is 3.

The trap is the change of scale. Prescriptions are written in nanograms per kilogram per minute, but the code counts half-milligrams. One milligram is 1,000,000 nanograms, so a dropped zero changes the claim by a factor of ten.

To turn a prescription into a daily amount, multiply the dose by the patient’s weight and by 1,440 minutes. Then divide by 1,000,000 to get milligrams. A 70 kg patient on 20 ng/kg/min receives 2,016,000 ng a day, which is about 2.02 mg. The chart follows that patient from the prescription to a month of billing units.

Over 30 days that patient needs about 60.5 mg, or roughly 121 units, before any discarded drug. Check a prior authorization quantity against that kind of estimate before the first claim goes out. Doses usually rise over time, so the approved quantity can fall behind the prescription.

Modifiers for J1325 claims

Which modifiers a J1325 line needs depends on who bills it. A DME supplier billing home infusion follows the External Infusion Pumps policy article (A52507). A practice or hospital billing drug it gave follows the general Part B drug rules.

Every epoprostenol vial is single-dose, so the CMS JW and JZ policy applies to separately payable claims. With a discard, bill two lines: the used units with no JW, then the discarded units with JW. CMS may return claims without the right modifier as unprocessable.

Say one 1.5 mg vial and two 0.5 mg vials are opened, 2.0 mg goes into the cassette and 0.5 mg is discarded. Bill 4 units on the first line and 1 unit with JW on the second.

NDC reporting for J1325

Report the 11-digit National Drug Code of the vial you used, in 5-4-2 format with the N4 qualifier. Medicaid programs require it on drug claims, and many commercial and Medicare Advantage plans do too. The CMS crosswalk for October 2026 lists eight NDCs under J1325.

The cartons print shorter forms, so pad them before they go on the claim. Flolan’s label reads 0173-0517-00, which becomes 00173-0517-00. Veletri’s 66215-403-01 becomes 66215-0403-01. A zero added in the wrong segment points to a different product and fails the NDC-to-HCPCS match.

Administration, pump and supply codes that pair with J1325

J1325 pays for the drug only. The pump, the supplies and any administration service are billed on their own lines. Which of these appear depends on the setting. Home infusion bills pump K0455 and its supplies, while an office infusion adds 96365.

An infusion started during an inpatient admission is a different case. The drug is paid within the hospital’s inpatient payment, so no separate J1325 line is paid for those days.

Medicare coverage criteria for epoprostenol

Medicare covers home epoprostenol under the External Infusion Pumps LCD (L33794). The pulmonary hypertension must not be secondary to pulmonary venous hypertension or to a respiratory disorder such as COPD. The patient must have primary pulmonary hypertension or a form secondary to a listed condition.

The listed conditions include connective tissue disease, thromboembolic disease of the pulmonary arteries, HIV infection, cirrhosis, diet drugs and congenital left-to-right shunts. The LCD then asks for four more findings:

• The pulmonary hypertension has progressed despite maximal medical and/or surgical treatment of the underlying condition
• Mean pulmonary artery pressure is above 25 mm Hg at rest or above 30 mm Hg with exertion
• The patient has significant symptoms, such as severe dyspnea on exertion with fatigability, angina or syncope
• Oral calcium channel blockers have been tried and failed, or were considered and ruled out

Commercial plans set their own criteria, usually through a pharmacy or medical clinical policy for epoprostenol. Check that policy, and whether the plan routes the drug through a specialty pharmacy, before the first fill.

Documentation that supports a J1325 claim

Infusion drug claims are audited against the record, so the chart has to show the coverage criteria and the dose math. For each J1325 claim, the record should hold:

• Diagnosis: the type of pulmonary hypertension, with the ICD-10-CM code that matches it
• Hemodynamics: the right heart catheterization result, including mean pulmonary artery pressure
• Symptoms and prior treatment: functional symptoms, treatments tried, and the calcium channel blocker decision
• Prescription: dose in ng/kg/min, current weight, concentration and infusion rate
• Product details: brand or generic, vial strengths, NDC, lot number and expiry
• Amounts: milligrams mixed, milligrams used and any discarded amount
• Equipment: the pump (K0455 for Medicare home use) and a backup pump plan

For the diagnosis, ICD-10-CM codes such as I27.0 (primary pulmonary hypertension) and I27.21 (secondary pulmonary arterial hypertension) describe Group 1 disease. Match the code to the documented cause, and keep the record consistent with clean claim standards.

Common J1325 denial reasons and how to fix them

Most J1325 denials trace back to units, modifiers or coverage evidence. The table maps the usual causes to their fixes. Systematic denial management starts with tracking which of these appears most often.

The full list of adjustment codes and their meanings is in our CARC denial codes reference.

Related codes to know when billing J1325

Several codes sit next to J1325 on pulmonary hypertension claims, and a few are easy to confuse with it.

How Pabau supports infusion drug billing

Practices that manage patients on epoprostenol juggle prescriptions, infusion visits and drug claims across several systems. Each hand-off is a chance to lose a unit, an NDC or a modifier.

Pabau, the practice management platform we build, keeps the clinical record and the claim in one place. Its claims management software sends CMS-1500 and 837P claims through the Claim.MD clearinghouse. It also runs eligibility checks and posts ERA remittances against the patient record.

Stock in Pabau carries a batch number and an expiry date, and the lot is recorded against the patient and the appointment. When a payer questions a J1325 line, the vial details sit beside the visit note and the claim.

Bill infusion drugs without losing units

Pabau keeps drug lots, visit notes and claims in one system, and submits claims through the Claim.MD clearinghouse. See how it handles drug billing for your practice.

Book a demo

Conclusion

J1325 claims succeed or fail on one conversion. The prescriber writes nanograms per kilogram per minute, and the payer counts half-milligrams. A practice that writes the milligrams mixed, used and discarded into the record can defend every unit on the claim.

The rest follows from the setting. Home infusion runs through K0455 with KX on every line, and an office infusion pairs with 96365. Book a demo to see how Pabau keeps the infusion record and the drug claim together.

Continue your research

Billing another prostacyclin for pulmonary arterial hypertension? HCPCS code J7686 covers inhaled treprostinil solution supplied through DME, with its units and claim rules.

Sending a nurse to manage the infusion at home? CPT code 99601 explains how to bill a home infusion visit for specialty drug administration.

Supplying batteries for a patient’s external infusion pump? HCPCS code K0601 sets out the billing rules for replacement infusion pump batteries.

Reviewing a patient’s full PAH regimen? Our pulmonary hypertension medication list groups the drugs by class in a free PDF.

Frequently asked questions