Rheumatology practices lose $94,000 to $160,000 a year from infusion billing errors alone — mostly incorrect infusion time documentation and missing J-code units — on medications where a single infusion visit can represent $8,000 to $25,000 in billed charges.
Common Billing Challenges
These are the six billing failure points we see most often in rheumatology practices — and the ones our team resolves systematically from day one.
Code 96366 only bills when additional infusion time exceeds 30 minutes past the hour. Misapplying this rule causes either undercoding — lost revenue — or overcoding, which creates audit risk.
Units are defined per the J-code descriptor, not per dose or vial. A single unit-count error on a high-dose infliximab infusion can mean $4,000 to $8,000 underpaid on that one claim.
Biosimilar versions carry distinct J-codes from the reference product. Billing the reference code for a biosimilar administered — or vice versa — is a compliance risk and a common audit trigger.
Payers require documented DMARD trials — drug, dose, duration, and reason for discontinuation — before approving a biologic. Incomplete documentation is the leading cause of authorization denials.
A denied biologic infusion claim costs $8,000 to $25,000 — far more than the cost of delaying treatment one cycle. Verbal approval isn't enough; printed authorization confirmation should be policy.
Correctly applying modifier 25 and coding E/M to the MDM level actually supported captures an additional $85 to $140 per infusion visit — without adding a single new service.
Key Procedure Codes
Our coders hold specialty-specific credentials and train continuously on the codes that drive the most revenue — and the most denials — in rheumatology.
| CPT/J-Code | Description | Common Issue |
|---|---|---|
| 96365 | IV infusion, therapeutic — initial, up to 1 hour | Requires at least 16 minutes to bill |
| 96366 | IV infusion, each additional hour (add-on) | Only bills when time exceeds 30 min into the next hour |
| 96367 / 96368 | Sequential / concurrent infusion | Concurrent bills one unit regardless of time |
| J1745 | Infliximab (Remicade), per 10mg | A 1000mg dose = 100 units; miscounts cost $4K–$8K/claim |
| J9312 | Rituximab (Rituxan), per 100mg | Bill per 100mg increments, verified against actual mg dose |
| Modifier 25 | Same-day E/M with infusion | Requires a separately identifiable, documented E/M service |
Why Rcmaxis
We're not a generalist billing service that added a specialty module. Our team is built around specialty-specific expertise.
Every coder on your account holds the specialty coding credential relevant to rheumatology infusion billing — not a generic CPC only.
Well above the errors driving a typical $94K-$160K annual loss in rheumatology — we verify J-code units and infusion time documentation on every claim before submission.
Full EHR integration, payer enrollment verification, and charge capture setup in 2 weeks — with zero disruption to your infusion suite.
One point of contact who knows your practice, your payers, and your billing history — available for weekly calls and monthly performance reviews.
Month-to-month engagement. We earn your business every month by improving your collections — not by locking you in.
Live visibility into your collections, denial rate, aging AR, and payer performance — updated daily, reviewed monthly with your account team.
Straight answers to what practices usually ask before they switch.
Free revenue assessment for qualified practices. We audit your last 90 days of claims, identify every revenue leak, and show you a clear path to better collections — at no cost.