96368 Case Study That Reduced AR Days in Infusion Billing

One of the most complex areas of medical billing is infusion billing. Just one line of code could mean claim denials, AR days, and more payments delayed. 96368 is one of those codes that seems straightforward at the surface, but can create serious billing issues if not coded properly.

This case study is a true example of an infusion practice that had a 40% denial rate on 96368 claims. They had now reached AR days of 48 and a significant portion of unpaid claims were directly attributable to this add-on code. The detailed denial analysis and structured correction plan helped the practice reduce their AR days to 29 within 90 days!

This blog will provide you with a walkthrough of how they were denied for each reason, exactly how they were fixed and the results they obtained. If you perform infusion services, this case study will help you recognize and overcome the same problems and lose revenue.

 

What is CPT 96368 in infusion Billing?

CPT 96368 is an add-on code that is included in infusion billing to document each subsequent IV push of a new drug or substance during the same encounter. It can only be billed with another primary infusion or push code, it is not reported independently.

This code will be used when a new and different drug has been given intravenously after the first push is reported. The focus is on new. In the event of the same drug continuing or recurring, 96368 is not applicable.

Common primary codes that 96368 is paired with include:

• 96374 (therapeutic, prophylactic, or diagnostic injection, IV push, single or initial substance)
• 96365 (intravenous infusion, initial up to one hour)
• 96375 (each additional sequential IV push of a new substance)

Because 96368 is an add-on code, it follows strict billing rules. Misunderstanding those rules is the number one reason practices face denials on this code.

 

Denial Reason 1: Billed as a Standalone Code

The Problem

The most common denial seen in this case study was 96368 submitted without any primary infusion or push code on the same claim. Since 96368 is strictly an add-on code, payers reject it automatically when there is no base code present. The billing team was submitting 96368 on its own in certain cases where the primary code was either missing from the encounter or accidentally left off the claim during data entry.

This error seems basic, but it is surprisingly common in busy infusion practices where claims are processed in high volumes and pre-submission audits are not in place.

The Fix

• Pair 96368 with a qualifying primary code always
• Use 96374, 96365, or 96375 as the base code
• Add billing software edits to flag solo 96368 claims
• Run a pre-submission audit to catch missing base codes
• Train billers on add-on code hierarchy rules

 

Denial Reason 2: Incorrect Unit Billing

The Problem

Another major denial pattern was incorrect unit reporting. The billing team was submitting multiple units of 96368 for a single encounter, assuming each individual syringe used during the visit counted as a separate billable unit. This is a common misunderstanding in infusion billing.

Payers, including Medicare, allow one unit of 96368 per additional sequential push of a new substance. The number of syringes used to administer a drug does not change the unit count. When multiple units were submitted without proper documentation to support them, payers denied the additional units as not medically necessary or as duplicate billing.

The Fix

• Bill one unit per new drug push only
• Do not count syringes as separate billable units
• Match units to clinical documentation always
• Review payer policies for unit limits per encounter
• Confirm each unit with the nursing infusion record

 

Denial Reason 3: Same Drug Billed Twice

The Problem

96368 is only valid when a new and different drug is administered via IV push after the primary push. In this practice, claims were being submitted where the same drug billed under the primary code was also being billed again under 96368. Payers denied these claims immediately because the code definition requires a new substance, not a repeated or continued administration of the same drug.

This error often happens when nursing documentation is vague and does not clearly identify each drug by name and time. The billing team was working from incomplete records and made incorrect code selections as a result.

The Fix

• Verify the drug under 96368 is a new substance
• Never bill the same drug under both base and add-on
• Require nurses to document each drug name clearly
• Review infusion records before finalizing the claim
• Match drug names in notes to codes on the claim

 

Denial Reason 4: Lack of Medical Necessity Documentation

The Problem

Several claims in this case study were denied not because of a coding error but because the medical record did not justify why a second drug was administered intravenously during the same visit. Payers require that each drug pushed under 96368 be medically necessary and clearly linked to a diagnosis.

When the physician order was missing, vague, or did not connect the drug to a specific diagnosis code on the claim, payers had no basis to approve payment. This is a documentation issue as much as it is a billing issue. The clinical team was not providing enough detail in their notes to support the billing team’s submissions.

The Fix

• Link each 96368 drug to a diagnosis code on the claim
• Ensure physician orders are complete and signed
• Document the reason for each drug in nursing notes
• Use specific ICD-10 codes that match the drug given
• Educate providers on documentation requirements

 

Denial Reason 5: Bundling with Chemotherapy Codes

The Problem

When 96368 was submitted alongside chemotherapy administration codes, payers applied NCCI (National Correct Coding Initiative) edits and either bundled the code or denied it entirely. Some members of the billing team were applying 96368 during chemotherapy encounters without first checking whether bundling restrictions applied.

NCCI edits exist to prevent duplicate payment for services that are considered part of a single procedure. When 96368 is billed with certain chemo codes, it may be considered bundled unless a valid reason exists to unbundle it. Without proper documentation and the correct modifier, those claims were denied consistently.

The Fix

• Check NCCI edits before billing 96368 with chemo codes
• Use modifier 59 or XS only when documentation supports it
• Never apply modifiers routinely without clinical backup
• Review payer bundling policies before claim submission
• Document separate and distinct services clearly in notes

 

Denial Reason 6: Missing or Incorrect Modifier

The Problem

A number of claims were denied due to modifier errors. Some claims were submitted without any modifier when one was required. Others had the wrong modifier attached, which caused the payer to either reject or deny the claim on technical grounds. Modifier errors are particularly problematic because they can be difficult to identify without a thorough EOB review.

In infusion billing, modifiers like 59, XS, and XU carry specific meanings. Using the wrong one, or skipping one entirely, signals to the payer that the service may be duplicated or improperly coded. The practice did not have a standardized modifier policy in place, which led to inconsistent submissions across different billers.

The Fix

• Build a modifier checklist for all infusion claims
• Learn when 59, XU, and XS each apply specifically
• Review EOBs to find the exact modifier causing denials
• Standardize modifier use across the entire billing team
• Never add a modifier without supporting documentation

 

Denial Reason 7: Timely Filing Missed Due to Rework Delays

The Problem

Even after the practice identified the denial reasons above, some corrected claims were never resubmitted on time. The original claims were denied, sat in a work queue too long, and by the time a biller addressed them, the payer’s timely filing deadline had already passed. This meant the practice lost that revenue permanently with no way to recover it.

Timely filing denials are particularly damaging because the service was provided, the coding may now be correct, but the window to collect has closed. The practice had no formal denial follow-up system and no alerts to flag aging claims that were at risk of crossing the filing deadline.

The Fix

• Set strict resubmission deadlines for all denied claims
• Assign 96368 denials to one dedicated biller
• Use your PM system to flag claims near filing limits
• Prioritize denials within 30 days of the deadline
• Track resubmission status weekly without exceptions

 

How Infusion Billing Services Helped This Practice?

In this case study, the practice was not able to turn things around alone. They partnered with Infusion Billing Services, a specialized billing company with deep expertise in infusion coding and denial management.

All 96368 claims were audited by our Infusion Billing Services team, their patterns of denials were identified and a customized plan for corrections was created. We collaborated directly with the clinical team to enhance documentation and provided retraining to the billing team in add-on code rules, modifier usage and payer-specific policies.

At  Infusion Billing Services, we don’t just correct current denials, but also established automated claim edits and a denial tracking system to avoid future losses. We played a role in the AR days being reduced from 48 to 29 in one quarter.

If your practice is struggling with the same issues as you are with infusion billing, then you have a solution that can help you cut down on denials, preserve your revenue, and support your workforce.

Conclusion

CPT 96368 is a small add-on code with a big impact on infusion billing revenue. As this case study shows, a single code can be responsible for a significant portion of your denials and a large increase in AR days when it is not billed correctly.

The seven denial reasons covered in this blog represent the most common mistakes infusion practices make with 96368. Each one has a clear and actionable fix. The practice in this case study applied every fix, partnered with infusion billing specialists, and reduced their AR days by nearly 40 percent in just three months.

If you are seeing high denial rates on 96368 or struggling with infusion AR days, start with a denial pattern analysis. Look at your last 90 days of 96368 claims, identify which denial reasons apply to your practice, and build a correction plan based on what you find.

The revenue is recoverable. The process is fixable. You just need the right strategy and the right team.