Authorization Units Exhausted: Preventing Therapy and Infusion Claim Denials

A prior authorization can still be active and a claim can still be denied.

That surprises many therapy clinics, infusion centers, and medical practices because authorization is often treated as a simple yes-or-no requirement. Once approval is obtained, staff may assume the treatment is financially protected until the authorization expiration date.

In reality, many authorizations contain several limits at the same time.

A payer may approve:

A specific date range
A fixed number of visits
A defined number of billing units
Certain CPT or HCPCS codes
A specific provider
A particular treatment frequency
A particular location
A specific drug dose or quantity

The authorization may therefore remain valid by date while the approved quantity has already been consumed.

When authorization units exhausted appears as the reason for a denial, the issue is usually not that the practice failed to obtain authorization altogether. The issue is that the payer believes the practice has already used the number of visits, units, treatments, or services it previously approved.

This creates a different billing problem and requires a different response.

For therapy and infusion practices, the risk is especially high because treatment plans can change during care. A patient may begin attending therapy more frequently, require additional units per session, receive a higher infusion dose, or continue treatment longer than originally expected.

If authorization tracking does not keep pace with those changes, services can continue after the payer’s approved quantity has already been exhausted.

The result may be medically necessary care that was delivered correctly but cannot be reimbursed because the administrative authorization limit was exceeded.

What Does “Authorization Units Exhausted” Mean?

Authorization units exhausted means the payer believes the provider has already used all of the visits, units, treatments, days, or other authorized quantities approved for the patient’s care.

For example, suppose a payer approves:

48 physical therapy units

during a three-month authorization period.

The patient receives four billable units during each therapy visit.

After 12 visits:

48 authorized units have been consumed.

The authorization period may still have several weeks remaining, but the quantity limit has been reached.

If another visit is performed and four additional units are billed, the payer may deny those units because the authorization has been exhausted.

This is an important distinction:

An authorization can be active by date but exhausted by quantity.

That is why practices should never monitor only the authorization start and end dates.

Authorization Approval Is Not Unlimited Approval

Prior authorization is usually approval for a defined scope of treatment.

A payer may specify exactly what it is willing to cover.

That scope might include:

CPT code: 97110
Approved units: 24
Date range: October 1 through December 31
Provider: Specific therapist or group
Frequency: Two sessions per week

If the practice submits services outside those limits, the payer may deny the claim even though an authorization number exists.

The existence of an authorization therefore does not prove that every related claim will be payable.

Billing teams need to determine whether the service submitted matches the full authorization.

PROMBS frequently sees authorization-related denials occur when the approved service and the billed claim are not fully aligned. A claim may contain the right authorization number but still differ from the approval in units, CPT codes, dates, provider, frequency, or treatment location.

Authorization Units vs. Visits: Why the Difference Matters

One of the most common sources of confusion is the difference between units and visits.

They are not necessarily interchangeable.

A Visit

A visit usually refers to one patient encounter.

For example:

A patient attends physical therapy once on Monday.

That is one visit.

A Unit

A unit is a billing quantity associated with a CPT, HCPCS, medication, time increment, or service.

A single visit may contain multiple units.

For example, a physical therapy session might include:

2 units of therapeutic exercise
1 unit of manual therapy
1 unit of neuromuscular reeducation

That is:

1 visit

but:

4 billed units

If the authorization approves 40 units, the practice cannot simply assume that means 40 visits.

At four units per visit, those 40 units could be consumed in approximately 10 visits.

This distinction is critical for authorization tracking.

How Therapy Units Can Be Exhausted Earlier Than Expected

Suppose a payer authorizes:

60 units of therapy

for a two-month period.

The original plan assumes three units per visit.

That would theoretically support:

20 visits

But the patient’s condition changes, and the therapist begins delivering four units during some sessions.

The authorized quantity is now being consumed faster.

If the scheduling team continues using the original assumption of 20 available visits, the clinic may unknowingly schedule services beyond the authorized amount.

This is why authorization tracking must reflect actual units delivered, not simply the number of visits that occurred.

Units, Visits, Days, Frequency, and Date Range Are Different Limits

Authorizations can be structured in different ways.

Understanding the approval language is essential.

Unit-Based Authorization

Example:

32 units approved

The practice must track billing units.

Visit-Based Authorization

Example:

12 visits approved

The practice must track completed encounters.

Day-Based Authorization

Example:

20 treatment days approved

Multiple services may occur on one authorized day depending on payer rules.

Frequency-Based Authorization

Example:

2 visits per week

The practice may have authorization for the overall period but still violate the approved frequency.

Date-Based Authorization

Example:

November 1 through January 31

Services performed outside this date window may deny.

Combination Authorization

Many payers use more than one limit.

For example:

24 visits, maximum four units per visit, between November 1 and February 28.

The practice must comply with all three limits.

This is why reading only the authorization expiration date creates unnecessary risk.

What Is an Authorization Quantity?

The authorization quantity is the amount of service the payer has approved.

Depending on the service, this may be expressed as:

Visits
Units
Sessions
Treatments
Hours
Days
Drug units
Infusions
Procedures

The approved quantity should be recorded in a centralized authorization tracking system so scheduling, clinical, billing, and authorization teams are working from the same information.

Why Claims Deny Even When Prior Authorization Was Approved

Authorization approval is only one part of the claim-payment process.

A claim may still deny if:

Approved units were exhausted
Approved visits were exhausted
Service occurred outside the authorization date range
Wrong CPT code was billed
More units were billed than approved
Treatment frequency exceeded the authorization
Provider does not match authorization
Facility does not match authorization
Authorization number was entered incorrectly
Payer counted prior claims differently
Duplicate claims consumed authorized quantity
Clinical treatment changed without authorization update

This is why practices should review authorization details throughout the course of treatment instead of treating authorization as a one-time front-end task.

CO-198: Authorization Exceeded

One of the most important denial codes associated with exhausted authorization limits is CARC 198.

This generally indicates that the authorization, notification, or precertification limit has been exceeded.

Practices may see it when:

Authorized visits are exhausted
Authorized units are exhausted
Approved service frequency is exceeded
Authorized treatment days have been consumed
Services occur outside approved limitations

The denial may also be accompanied by payer-specific remark codes providing more detail about the quantity or date issue.

The key point is that CO-198 is not the same as having no authorization at all.

CO-197 vs. CO-198

These denial codes are commonly confused.

CO-197

Generally indicates that authorization, notification, or precertification was missing or not obtained.

The core issue is:

Authorization absent.

CO-198

Generally indicates that authorization existed but the approved limit was exceeded.

The core issue is:

Authorization exhausted or exceeded.

This distinction matters because the corrective action is different.

For CO-197, the practice may need to determine whether authorization was actually required, whether one existed but was not linked correctly, or whether retro authorization is possible.

For CO-198, the practice should investigate:

Approved quantity
Units already consumed
Visits already processed
Payer claims history
Reversals
Duplicate claims
Reauthorization status
Changes to treatment

A simple authorization-number correction may not resolve an exhausted-unit denial.

Why Payer Records and Practice Records May Not Match

Another major challenge is that the practice and payer may show different remaining authorization quantities.

The clinic may believe eight units remain.

The payer portal may show zero.

This can happen because:

A previously submitted claim consumed units
Duplicate claims were counted
A corrected claim was counted incorrectly
A reversal has not restored units
The practice failed to record a prior visit
The payer counted units differently
An authorization amendment was not loaded correctly
Different CPT codes are drawing from the same authorization pool

When the records do not match, the billing team should not assume the payer is correct or that the internal tracker is correct.

The unit history must be reconciled.

Authorized, Scheduled, Delivered, Billed, and Adjudicated Units

One of the strongest ways to prevent authorization denials is to separate five different quantities.

Authorized Units

What the payer approved.

Example:

40 units

Scheduled Units

What the practice plans to deliver.

Example:

10 future sessions × 4 units = 40 scheduled units

Delivered Units

What the clinician actually performed.

A scheduled four-unit visit may end after three units because the patient cannot tolerate the full session.

Delivered units:

Billed Units

What the billing department submits on the claim.

The claim should reflect the documented service actually delivered.

Adjudicated Units

What the payer’s claims system ultimately processes against the authorization.

These five numbers can diverge.

That is where many authorization problems begin.

Why Scheduling Alone Cannot Track Authorization Usage

Scheduling systems usually track visits.

Billing systems usually track claim units.

Clinical documentation tracks what was actually performed.

Payer portals track what the payer counted.

If these systems operate independently, staff may believe authorization is still available when the payer has already consumed the approved quantity.

For example:

Authorization: 48 units

Scheduling dashboard:

10 visits completed

The team assumes two visits remain because it expects 12 visits total.

But actual billing shows:

Six visits at 4 units = 24 units
Four visits at 6 units = 24 units

Total:

48 units consumed

The authorization is already exhausted after only 10 visits.

Without unit-level reconciliation, scheduling may continue treatment under the assumption that approval remains.

Why Therapy Practices Are Especially Vulnerable

Physical therapy, occupational therapy, speech therapy, ABA, and other recurring treatment models face elevated authorization risk because patients may receive care multiple times per week over extended periods.

The quantity used during one encounter may also vary.

Physical Therapy

A visit may contain multiple time-based CPT units.

Treatment intensity can change as the patient progresses.

Occupational Therapy

Different combinations of therapeutic activities and interventions may affect unit consumption.

Speech Therapy

Some payers authorize visits while others authorize specific service quantities or date ranges.

ABA Services

Authorization may be separated by service type, provider type, CPT code, or number of units.

A clinic might have authorization remaining for one ABA service but no units remaining for another.

The recurring nature of therapy creates more opportunities for approved quantities to be exhausted before the authorization end date.

Therapy Visit Limits and Authorization Limits Are Not Always the Same

Practices should distinguish between:

Benefit limits

and:

authorization limits

A health plan may allow a certain number of therapy visits annually as a benefit.

Separately, the payer may issue authorization for only a portion of those visits at one time.

For example:

Annual benefit:

30 PT visits

Current authorization:

8 visits

The fact that the patient has 22 benefit visits remaining does not mean the clinic can continue after the eight authorized visits are exhausted.

Another authorization may still be required.

This distinction should be verified during eligibility and authorization review.

Why Changes in Therapy Frequency Matter

Treatment plans often evolve.

A patient may originally be scheduled:

twice weekly

but later require:

three visits per week

for a period of time.

If the payer authorized a limited number of units or visits based on the original treatment plan, the increased frequency may exhaust the approval earlier.

The clinical team may view the frequency increase as medically necessary.

The authorization team needs to view it as a utilization change that may require payer notification or reauthorization.

The communication between these teams is essential.

Why Infusion Authorization Is More Complex

Infusion billing presents a different set of authorization risks.

A payer may authorize:

Specific medication
J-code
Drug quantity
Dose
Frequency
Number of infusions
Date range
Administration service
Site of care

An infusion authorization may therefore be affected by changes in treatment that do not occur as frequently in ordinary office billing.

Drug Units Are Not the Same as Infusion Visits

A payer may authorize a drug based on HCPCS units rather than the number of infusion appointments.

For example, assume a medication’s HCPCS code represents:

10 mg per billing unit

The patient receives:

300 mg per infusion

That requires:

30 drug units

If the payer authorizes 180 drug units, the authorization may support:

6 infusions at the original dose

Now suppose the physician increases the dose to:

400 mg

The same authorization will be consumed faster.

At 40 units per infusion, 180 authorized units no longer support six full treatments.

If the authorization is not amended, later claims may deny even though the treatment plan and authorization dates are still active.

Dose Changes Can Exhaust Infusion Authorization Early

Dose changes are one of the biggest authorization risks in infusion billing.

Clinical dosing may change because of:

Patient weight
Response to treatment
Lab values
Disease progression
Physician decision
Protocol changes

A change that is clinically appropriate can still change the billing quantity.

Therefore, authorization should be reviewed whenever the dose changes.

The clinical team should not assume that authorization automatically expands with the prescription.

Frequency Changes Can Also Affect Infusion Authorization

An infusion originally authorized every eight weeks may later be ordered every six weeks.

That changes utilization.

Even if the medication and dose remain identical, the authorized quantity may be consumed sooner than planned.

The authorization team should review whether:

Current approval allows the new frequency
Additional treatments are required
New authorization is needed
Existing quantity must be amended

If this review happens only after claims deny, the practice has already accepted financial risk.

Medication Changes Can Invalidate the Original Authorization

A patient may switch from one drug to another during the treatment course.

The original authorization may apply only to the first medication.

Even if the new therapy treats the same condition, the payer may require:

New authorization
New J-code approval
Updated medical necessity documentation
Step-therapy evidence
New dose information

The billing department should verify authorization before billing the replacement drug.

Route of Administration Can Matter

Some authorizations are tied to a specific route of administration.

A payer may approve:

IV infusion
Subcutaneous administration
Injection

A route change may alter:

Drug code
Administration code
Site-of-care requirement
Billing units
Authorization requirements

The authorization should therefore be reviewed whenever the treatment route changes.

Treatment Duration Can Outgrow the Original Authorization

Many chronic therapy and infusion patients continue treatment longer than initially expected.

The original authorization may cover:

8 weeks

while the clinician later determines the patient needs:

12 weeks

If the extension is not requested before the initial authorization expires or units are exhausted, the additional services may be at risk.

This is why reauthorization should not begin only when the last approved service has already been performed.

Duplicate Claims Can Affect Authorization Unit Counts

Duplicate claims create another complication.

A practice may accidentally submit the same claim twice.

The payer may deny one as duplicate, but in some cases the payer’s utilization system may temporarily or incorrectly count both transactions against authorization.

Similarly, corrected and replacement claims may not always restore authorized units immediately.

This can create a situation where:

Practice tracker shows units remaining
Payer portal shows units exhausted

The billing team should review:

Original claim
Duplicate claim
Replacement claim
Reversal
Payer adjudication history
Authorization utilization history

Do not assume that every exhausted-unit denial means the patient truly received more treatment than was approved.

Voids and Reversals May Not Immediately Restore Units

If a claim is voided, the practice may expect the corresponding authorization units to become available again.

That does not always happen immediately.

The payer’s claims system and authorization system may update at different times.

Before resubmitting services, confirm that the units have actually been restored.

Otherwise, the corrected claim may deny again.

CPT Changes Can Consume a Different Authorization Bucket

Some authorizations apply only to specific CPT codes.

For example:

Authorization may approve:

97110
97112

but not:

97140

If treatment changes and the clinician begins performing another service, the claim may deny even though overall units remain.

Other payers may create a combined unit pool shared across multiple CPT codes.

The practice must know which model applies.

Provider Changes Can Affect Authorization Validity

An authorization may be connected to:

Rendering provider
Billing provider
Group NPI
Facility
Location

If a therapist leaves or treatment moves to another location, the authorization may need to be updated.

The unit count may be sufficient, but the claim can still deny because the provider details no longer match the authorization.

That is why authorization management should track more than quantity alone.

Insurance Changes Can Reset the Entire Authorization Process

If the patient’s insurance changes during therapy or infusion treatment, the existing authorization may no longer apply.

The new payer may have different requirements for:

Authorization
Units
Visits
Documentation
Frequency
Drug coverage
Site of care

Eligibility should therefore be rechecked regularly for long treatment courses.

Continuing care under an old authorization after coverage changes can result in multiple denials.

Why Authorization Exhaustion Often Produces Multiple Denials

Recurring treatment means one missed authorization threshold can affect more than one claim.

Suppose authorization runs out on March 10.

The clinic does not discover the issue until April 5.

During that period, the patient completes:

4 therapy visits
16 units

Instead of one denial, the practice may now have four denied claims.

If several patients are affected by the same weak tracking workflow, the revenue impact can multiply quickly.

This is why authorization exhaustion should be treated as a process-control problem, not simply an individual denial.

The Financial Impact Goes Beyond the Denied Claim

An exhausted authorization can lead to:

Delayed reimbursement
Staff rework
Reauthorization effort
Appeal preparation
Patient billing disputes
Write-offs
Increased A/R
More payer calls
Interrupted treatment planning

In some cases, retroactive authorization may not be available.

That can turn a preventable administrative failure into unrecoverable revenue.

The Core Prevention Principle

The most important concept is to stop thinking of authorization as a document that is obtained once and filed away.

Authorization should be treated as an actively managed resource.

For every patient, the practice should know:

What was approved?

How much was approved?

What has been delivered?

What has been billed?

What has the payer counted?

How much remains?

When should reauthorization begin?

That is the foundation of preventing authorization units exhausted denials.

How to Track Authorization Units Before They Run Out

Preventing authorization-related denials requires more than storing an authorization number in the patient’s chart.

The practice needs a structured workflow that connects:

authorization → scheduling → clinical delivery → billing → payer adjudication

If those steps are disconnected, a patient can continue receiving medically necessary care even after the payer’s approved quantity has already been consumed.

The strongest authorization process therefore does not ask only:

“Do we have an authorization?”

It also asks:

“How much authorization remains right now?”

For therapy and infusion practices, this should be monitored throughout the entire course of treatment.

Step 1: Record the Complete Authorization

Every approval should be entered into a centralized authorization tracker.

At minimum, capture:

Patient name
Member ID
Payer
Authorization number
Approved CPT or HCPCS codes
Approved units
Approved visits
Start date
End date
Frequency
Rendering provider
Billing provider
Facility/location
Diagnosis when relevant
Drug name
J-code when relevant
Approved dose
Site-of-care restriction
Authorization status
Reauthorization deadline

Do not rely on a single field called:

“Authorization approved.”

That does not provide enough information to prevent an authorization units exhausted denial.

Step 2: Identify What the Payer Is Actually Counting

Before care begins, determine whether the payer measures utilization by:

Visits
Units
Treatment days
Hours
Procedures
Drug quantity
Infusions
CPT-specific units
Combined unit pools

This sounds basic, but many authorization failures begin because the practice is counting visits while the payer is counting units.

Example

The payer approves:

48 units of physical therapy

The clinic records:

12 visits approved

That assumption is valid only if each visit uses exactly four units.

If some visits contain five or six units, the authorization will be exhausted earlier.

The practice should therefore track the same quantity the payer tracks.

Step 3: Convert Authorization Into an Operational Limit

Authorization information must be translated into something the clinical and scheduling teams can use.

For example:

Authorized quantity:

48 units

Typical visit:

4 units

Estimated capacity:

12 visits

But the tracker should not permanently convert this into “12 visits” and stop monitoring units.

Instead, staff can use the 12-visit estimate for planning while continuing to subtract the actual units delivered from the original 48-unit authorization.

Example

Visit 1: 4 units
Visit 2: 4 units
Visit 3: 3 units
Visit 4: 5 units

Total consumed:

16 units

Remaining:

32 units

The exact unit count is more accurate than saying simply:

4 visits completed.

Step 4: Connect the Authorization to Scheduling

Schedulers should be able to see the authorization status before adding future appointments.

Useful scheduling alerts include:

Authorization active

Authorization expires soon

75% of units used

90% of units used

No authorized units remaining

Reauthorization pending

The scheduler should not need to manually search through payer documents every time a visit is booked.

The information should be visible where appointments are being created.

Step 5: Reserve Enough Units for Scheduled Visits

A common mistake is comparing only:

units already used

against:

total units approved

without considering future appointments that are already booked.

Suppose:

Authorized units: 40
Used units: 28
Remaining units: 12

The practice may think authorization is safe.

But the patient already has four future visits scheduled at approximately four units each.

Scheduled demand:

16 units

Available:

12 units

The authorization is already insufficient to cover the planned treatment schedule.

A strong tracker therefore monitors:

Remaining units vs. scheduled units

rather than only:

Remaining units vs. zero

Step 6: Track Actual Delivered Units

Scheduling predicts utilization.

Clinical documentation confirms what actually happened.

After every visit, the authorization tracker should be updated with the actual units delivered.

For therapy, that may include:

Therapeutic exercise
Manual therapy
Neuromuscular reeducation
Therapeutic activities
Gait training
Other authorized services

The number of units should come from the final clinical documentation, not from what was originally scheduled.

Step 7: Reconcile Delivered Units With Billed Units

The next step is to compare what clinicians documented with what the billing team submitted.

If the therapist delivered three units but four units were billed, the authorization may be consumed faster than the actual care delivered.

That can create both:

Authorization problems
Coding/compliance problems

The practice should monitor:

Delivered units = documented units = billed units

when payer and coding rules support that relationship.

Any mismatch should be investigated.

Step 8: Reconcile Billed Units With Payer-Adjudicated Units

This is the step many practices miss.

The internal tracker may show that 36 units have been billed.

The payer may show that 40 units have been counted against the authorization.

That four-unit difference should be investigated before the next claim is submitted.

Possible causes include:

Duplicate claim
Corrected claim counted twice
Reversal not restored
Payer system error
Previous claim not entered internally
Different CPT mapping
Payer counting rules

The most accurate authorization workflow therefore tracks:

Quantity	Meaning
Authorized	Payer-approved maximum
Scheduled	Planned services
Delivered	Services actually performed
Billed	Units submitted on claims
Adjudicated	Units payer counted
Remaining	Payer-approved quantity still available

This reconciliation model is one of the strongest ways to prevent unexpected CO-198 denials.

Step 9: Create Utilization Threshold Alerts

Do not wait until 100% of authorization is consumed.

Practices should establish internal alert thresholds.

A useful framework may be:

50% Used

Routine monitoring.

75% Used

Review treatment plan and expected remaining course.

80% Used

Determine whether additional authorization will likely be required.

90% Used

Reauthorization should generally be actively underway when continued care is expected.

100% Used

Do not schedule or deliver additional authorization-dependent services without confirming coverage.

The exact thresholds can vary based on payer lead times and treatment frequency.

Step 10: Start Reauthorization Early

Reauthorization should not begin after the final approved unit has already been delivered.

The right timing depends on:

Payer processing time
Documentation requirements
Frequency of visits
Treatment intensity
Remaining units
Clinical plan
Practice experience with that payer

A patient attending therapy three times weekly may consume the remaining authorization far faster than someone seen once every two weeks.

Therefore, reauthorization thresholds should consider both:

units remaining

and:

rate of utilization

Use Burn Rate to Predict Authorization Exhaustion

A useful metric is the patient’s authorization burn rate.

For example:

Authorization:

60 units

Average consumption:

5 units per visit

Visits per week:

Weekly burn rate:

15 units

If 30 units remain, the practice has roughly:

2 weeks of authorization left

This is far more useful than simply knowing:

50% remains

because it tells staff when the approval is likely to run out.

Step 11: Forecast the Exhaustion Date

The practice can calculate an estimated exhaustion date using:

Remaining units ÷ average weekly utilization

For example:

Remaining units: 24
Average weekly use: 8

Estimated remaining authorization:

3 weeks

If the payer generally takes 10 business days to process reauthorization, staff should begin the next request immediately.

This turns authorization management into a proactive workflow instead of a denial-recovery workflow.

Step 12: Monitor Authorization Expiration Separately From Unit Exhaustion

A patient may have:

Units remaining but authorization expired
Authorization active but units exhausted

Both situations can cause denials.

The tracker should therefore contain two separate alerts:

Date Alert

Authorization approaching expiration.

Quantity Alert

Authorized units approaching exhaustion.

These should never be merged into one generic authorization status.

Step 13: Review Authorization Whenever the Treatment Plan Changes

Clinical changes should trigger an authorization review.

Examples include:

Increased therapy frequency
Additional CPT codes
Longer sessions
New therapist
New treatment location
Additional discipline
Medication dose increase
Drug change
Infusion frequency change
Administration route change

The authorization team should receive these changes before the new service is delivered whenever possible.

Therapy Authorization Tracking Example

Suppose a payer authorizes:

72 physical therapy units

Authorization period:

January 1 through March 31

Original treatment plan:

3 visits per week

Expected units per visit:

The practice estimates:

72 ÷ 4 = 18 visits

After the first eight visits, actual use looks like this:

Visit	Units
1	4
2	4
3	5
4	5
5	4
6	5
7	4
8	5

Total used:

36 units

The patient has used:

50% of the authorization

after only eight visits.

If the clinic continues averaging 4.5 units per visit, the authorization may support only another eight visits rather than the 10 visits staff originally expected.

The authorization end date may still be months away, but unit exhaustion may occur much earlier.

Physical Therapy Authorization Controls

For PT practices, useful controls include:

CPT-specific authorization tracking
Timed-unit tracking
Visit frequency monitoring
Plan-of-care review
Remaining-unit alerts
Reauthorization work queues
Payer portal reconciliation

Authorization should also be reviewed when the patient’s plan of care changes.

Occupational Therapy Authorization Controls

OT practices should monitor:

Approved units
CPT combinations
Frequency changes
New functional goals
Treatment extension
Plan-of-care updates

As with PT, different services within the same visit may consume authorization differently.

Speech Therapy Authorization Controls

Speech therapy may be authorized by:

Visits
Sessions
Units
Date span

The practice should confirm the payer’s counting methodology before assuming that one visit equals one authorized unit.

ABA Authorization Tracking

ABA authorizations may be especially complex because different CPT codes may have separate unit pools.

For example:

Technician-delivered therapy
Supervisory services
Caregiver training
Assessment

A patient may still have units available for one code while another authorized service is fully exhausted.

The tracker should therefore be CPT-specific when the payer authorization is CPT-specific.

Step 14: Track Infusion Drug Units Separately From Administration Services

Infusion billing frequently involves at least two authorization components:

Drug
Administration

The payer may approve the medication but require separate authorization for administration, or vice versa.

Practices should therefore track:

Drug J-code
Drug units
Approved dose
Administration CPT
Number of treatments
Frequency
Authorization period
Site of care

Do not assume one authorization covers every part of the infusion claim.

Convert Infusion Dose Into Billing Units

Infusion practices should know exactly how the prescribed dose translates into HCPCS units.

Example:

HCPCS descriptor:

10 mg = 1 billing unit

Prescribed dose:

500 mg

Claim quantity:

50 units

If authorization approves:

300 units

the practice may have enough drug authorization for:

6 treatments

at the current dose.

A dose increase changes that calculation immediately.

Infusion Authorization Example

Authorization:

300 drug units

Original dose:

500 mg

HCPCS unit:

10 mg

Units per infusion:

500 ÷ 10 = 50 units

Expected treatments:

300 ÷ 50 = 6 infusions

After three treatments, the physician increases the dose to:

700 mg

New units per infusion:

700 ÷ 10 = 70 units

Units already used:

150

Remaining authorization:

150

The remaining authorization can now cover only:

2 full 70-unit infusions

with 10 units left.

If the practice continues planning three more treatments based on the original six-infusion assumption, the last claim may deny for exhausted units.

The authorization team should request additional quantity when the dose changes.

Step 15: Recalculate Authorization After Dose Changes

Whenever infusion dose changes, staff should calculate:

New units per treatment
Remaining authorized units
Number of treatments remaining
Expected exhaustion date

This should happen before the next claim is submitted.

Step 16: Review Authorization After Frequency Changes

Suppose an infusion is approved every eight weeks.

The physician changes it to every six weeks.

The same authorization quantity will now be consumed more quickly.

Staff should determine whether:

The existing authorization permits the frequency change
More treatments are needed during the authorization period
Additional units must be approved
New clinical documentation is required

Step 17: Review Authorization When Medication Changes

A medication change should trigger a completely new authorization review.

Verify:

New drug coverage
J-code
Units
Step therapy
Medical necessity
Site of care
Dose
Frequency
Administration services

Do not assume approval for Drug A covers Drug B.

Step 18: Review Site-of-Care Requirements

Infusion payers increasingly use site-of-care restrictions.

An authorization may be valid only for:

Hospital outpatient department
Physician office
Freestanding infusion center
Home infusion

If the patient moves to another site, the authorization may require amendment even when units remain.

Step 19: Track Pending Authorization Requests

A reauthorization request should have a clear status.

Useful statuses include:

Not started
Documentation requested
Submitted
Pending payer review
Additional information requested
Approved
Partially approved
Denied
Peer-to-peer requested
Appeal pending

The patient’s upcoming schedule should be reviewed against this status.

Step 20: Do Not Confuse Submitted Reauthorization With Approved Reauthorization

Submitting a request does not mean services are automatically covered.

If the previous authorization is exhausted and the new request is pending, practices should understand the financial risk of continuing treatment.

The decision may depend on:

Payer policy
Clinical urgency
Contract terms
Patient communication
Retro-authorization availability

The billing team should not assume approval simply because the request was sent.

What Documentation Supports Reauthorization?

Payers may request:

Updated plan of care
Progress notes
Functional improvement
Medical necessity documentation
Treatment goals
Response to therapy
Previous utilization
Physician order
Updated dose
Lab results
Failed treatment history

The exact requirements vary by payer and service.

Practices that begin collecting this documentation only after units are exhausted create avoidable delays.

Build a Reauthorization Documentation Checklist

The authorization team can maintain a checklist by payer.

Example:

Therapy

Current progress note
Updated plan of care
Functional outcome score
Physician signature if required
Units used
Units requested
Treatment frequency

Infusion

Current order
Diagnosis
Drug
Dose
Frequency
Relevant labs
Previous response
Medical necessity
Units requested

This shortens turnaround time when reauthorization begins.

Step 21: Create Payer-Specific Authorization Rules

Not every payer counts authorization the same way.

The practice should maintain payer rules for:

Unit calculation
Visit limits
Prior authorization thresholds
Reauthorization lead time
Retro authorization
Required documentation
Portal workflow
Authorization phone/fax
CPT-specific requirements
Drug-specific requirements

A generic authorization process is rarely enough for high-volume therapy or infusion billing.

Step 22: Audit the Payer Portal Before the Final Authorized Visit

Before the patient reaches the expected final approved service, confirm payer-side utilization.

Check:

Units used
Units remaining
Date range
CPT codes
Provider
Authorization status
Amendment status
Recent claims

This gives the practice time to investigate any mismatch before more care is delivered.

Step 23: Reconcile Duplicate Claims and Voids

If payer usage appears higher than expected, investigate:

Duplicate claims
Corrected claims
Voids
Reversals
Reprocessed claims

The payer may have counted units that should have been restored or removed.

Do not immediately assume the practice delivered unauthorized care.

Step 24: Establish Authorization Ownership

One of the biggest operational failures is unclear responsibility.

Who owns the authorization?

Possible teams include:

Front desk
Scheduling
Clinical staff
Authorization team
Billing department
RCM vendor

One person or team should have clear responsibility for monitoring:

Usage
Expiration
Reauthorization
Payer updates
Unit discrepancies

Shared responsibility without defined ownership often becomes no responsibility.

Step 25: Use Daily or Weekly Authorization Work Queues

Depending on volume, work queues can include:

Units below 25% remaining

Authorization expires within 14 days

Reauthorization pending

Payer discrepancy

Zero units remaining

Treatment-plan change

New insurance

Dose change

This allows staff to focus on accounts with the highest denial risk.

Common Authorization Tracking Failures

Tracking Only Expiration Dates

The authorization may remain active by date after units are exhausted.

Tracking Visits Instead of Units

One visit may consume multiple units.

Not Updating Actual Units

Expected utilization and actual utilization can differ.

Ignoring Future Scheduled Services

Remaining units may already be insufficient for appointments booked.

Starting Reauthorization Too Late

The payer may not approve additional care before units run out.

Clinical and Billing Teams Do Not Communicate

Dose, frequency, or treatment changes may never reach authorization staff.

Duplicate Claims Affect Payer Utilization

Internal records and payer records become inconsistent.

Payer Portal Is Never Reconciled

The clinic discovers the mismatch only after denial.

The Best Authorization Workflow Is Predictive

The goal should not be to discover that authorization has run out.

The goal should be to predict when it will run out.

A strong workflow uses:

Approved quantity → actual utilization → future schedule → burn rate → reauthorization lead time

That allows the practice to intervene before the patient reaches the authorization limit.

For therapy and infusion services, this is one of the most effective ways to prevent authorization units exhausted denials before they affect reimbursement.

What to Do When a Claim Denies for Authorization Exceeded

When a claim denies because authorization units are exhausted, the first step is not to immediately rebill or appeal.

The practice should first determine whether the payer’s unit count is correct.

An authorization units exhausted denial can result from a legitimate overutilization, but it can also be caused by:

Duplicate claims
Incorrect payer unit counting
Missing reversals
Corrected claims not restoring units
Wrong authorization loaded
CPT mismatches
Authorization amendments not applied
Provider or location mismatches
Services billed outside the approved quantity

That means every CO-198 denial should begin with reconciliation.

Step 1: Confirm the Denial Code

Review the ERA, EOB, payer portal, and claim status.

Look for:

CARC 198
Related remark codes
Authorization number
Quantity billed
Date of service
CPT or HCPCS code
Payer claim reference

The goal is to determine whether the denial is truly based on exceeded authorization or another authorization-related issue.

Step 2: Verify the Original Authorization

Retrieve the original approval and confirm:

Authorization number
Approved service
CPT/HCPCS
Units
Visits
Start date
End date
Provider
Location
Frequency
Drug
Dose
Site of care

Do not rely only on what was entered into the practice-management system.

Review the payer’s actual authorization record.

Step 3: Recalculate Units Used

Reconstruct the authorization history from the first approved service through the denied claim.

Compare:

Authorized units
Delivered units
Billed units
Adjudicated units

This often reveals where the discrepancy occurred.

Example

Authorization:

48 units

Internal tracker:

44 units used

Payer portal:

48 units used

Denied claim:

4 additional units

The payer may appear correct at first.

But the practice discovers that one previous four-unit claim was submitted twice.

If the payer counted both claims against the authorization, the true clinical utilization may still be only 44 units.

That becomes a payer correction issue rather than a genuine exhausted authorization.

Step 4: Check for Duplicate Claims

Duplicate claims can distort authorization utilization.

Look for:

Same date of service
Same CPT
Same units
Same claim number
Duplicate replacement claims
Corrected claims processed as new claims
Duplicate portal submissions

If the payer’s authorization balance was reduced by an invalid duplicate claim, request correction.

Step 5: Check Voids and Reversals

A voided claim should not permanently consume authorization units if the payer’s rules require those units to be restored.

However, payer systems may not update immediately.

Review:

Original claim
Void
Reversal
Replacement claim
Payer utilization balance

If the payer reversed the claim financially but did not restore units, contact the payer before assuming the authorization is truly exhausted.

Step 6: Confirm Whether the Claim Used the Correct Authorization

Patients may have multiple authorization records.

For example:

One authorization for PT
Another for OT
Separate approval for a specific CPT
Separate approval for a new treatment period

The payer may have linked the claim to the wrong authorization.

If another valid authorization exists, the claim may need correction or payer reprocessing rather than additional approval.

Step 7: Check the CPT or HCPCS Code

Authorization may be code-specific.

If the payer authorized:

97110

but the claim includes:

97140

the payer may deny the additional service even though overall authorization remains.

For infusion, verify:

J-code
Drug units
Administration code
Dose
Frequency

A code mismatch may look like an exhausted authorization when the real issue is that the billed service was not included in the approval.

Step 8: Review Date Range and Frequency

A claim may deny because the service exceeded an approved frequency even when the total units have not technically reached zero.

For example:

Authorization:

12 visits over 6 weeks

Approved frequency:

2 visits per week

If the patient receives three visits during one week, the payer may deny one visit depending on plan rules.

Always review both:

quantity

and:

frequency

Step 9: Determine Whether Additional Units Can Be Requested

If the authorization was legitimately exhausted but treatment remains medically necessary, determine whether the payer allows additional units.

The request may require:

Progress notes
Updated treatment plan
Medical necessity documentation
Functional improvement
Current physician order
Units already used
Additional units requested
Updated frequency
Expected treatment duration

The sooner this process begins, the lower the risk of interruptions and denials.

Can Additional Authorization Units Be Requested After Exhaustion?

Sometimes.

It depends on:

Payer policy
Plan type
Service
Reason for delay
Clinical urgency
Documentation
Contract rules

Some payers may allow additional authorization prospectively only.

Others may consider retroactive requests in limited circumstances.

Practices should never assume retro authorization will be granted.

Can Authorization Be Added Retroactively?

Retro authorization policies vary considerably.

Possible situations where a payer may review a retro request include:

Emergency or urgent treatment
Payer system error
Incorrect payer information
Coverage discovered after service
Authorization was submitted but not processed
Administrative delay outside the provider’s control

However, routine failure to monitor remaining units may not qualify.

That is why prevention remains more reliable than denial recovery.

Step 10: Determine Whether an Appeal Is Appropriate

An appeal may be appropriate when:

Units were not actually exhausted
Payer counted duplicate claims
Reversal did not restore units
Valid authorization was not applied
Payer processed against the wrong authorization
Authorization amendment was approved but not loaded
Medical necessity supports additional treatment
Payer guidance supports retro review

The appeal should directly address the reason for denial.

How to Appeal a CO-198 Denial

A strong appeal package may include:

Authorization approval letter
Authorization number
Approved units
Unit-utilization ledger
Claim history
ERA/EOB
Clinical notes
Updated treatment plan
Medical necessity documentation
Payer portal screenshots
Reauthorization request
Proof of duplicate or reversed claim activity
Relevant payer correspondence

The appeal should clearly explain:

What was approved

What was delivered

What the payer counted

Why the denial is incorrect or why additional units should be considered

Therapy Denial Recovery

For PT, OT, speech therapy, or ABA, begin with the authorization ledger.

Compare:

Visits approved
Units approved
CPT-specific limits
Visits completed
Units delivered
Units billed
Units adjudicated

Then determine whether the denial resulted from:

True exhaustion
Unit-count mismatch
Frequency issue
CPT issue
Date range
Provider mismatch
Reauthorization delay

Therapy Example

Authorization:

40 units

Practice tracker:

36 used

Denied claim:

4 units

Payer portal:

40 used before denied claim

The audit shows one earlier claim was submitted twice.

Correct action:

Request payer correction of authorization utilization and reprocessing of the denied claim.

Incorrect action:

Request unnecessary new authorization without correcting the duplicate count.

Infusion Denial Recovery

Infusion denials require additional review because billing quantity may be tied to:

Drug dosage
HCPCS units
Waste
Administration services
Frequency
Site of care

Infusion Example

Authorization:

240 drug units

Original dose:

40 units per infusion

Expected treatments:

After four treatments, dose increases to:

60 units

Units consumed after four treatments:

160

Remaining:

The fifth treatment uses 60 units.

Remaining:

The sixth treatment requires another 60 units.

Only 20 remain.

The sixth claim may deny unless additional units were approved.

In this case, the problem is not payer error.

The treatment plan changed and authorization was not updated.

What If the Payer Portal Shows Zero Units but the Practice Shows Units Remaining?

Treat this as a reconciliation issue.

Review:

Duplicate claims
Corrected claims
Voids
Reversals
Payer adjudication history
Authorization amendments
CPT-specific unit pools
Prior dates of service

Do not continue billing blindly.

Resolve the discrepancy before additional services are delivered whenever possible.

Preventing Repeat Authorization Denials

Once a denial is resolved, the practice should identify why the problem happened.

Possible root causes include:

Authorization not tracked
Wrong unit conversion
Clinical changes not communicated
Scheduling exceeded available units
Duplicate claims
Reauthorization started too late
Payer portal not reconciled
Staff relied only on expiration date
Payer-specific rules not documented

The prevention strategy should address the root cause.

Build Authorization Controls Across the Entire Revenue Cycle

Authorization management should involve more than one department.

Front Desk

Verify active insurance.

Scheduling

Check remaining authorization before booking.

Clinical Team

Communicate treatment-plan changes.

Authorization Team

Monitor usage and reauthorization.

Billing Team

Confirm claim quantity and denial feedback.

RCM Team

Reconcile payer utilization and recover denials.

The strongest process connects all of these functions.

Authorization KPIs Practices Should Track

Practices should measure authorization performance like any other revenue-cycle function.

Useful metrics include:

Authorization Denial Rate

Percentage of claims denied for authorization-related reasons.

CO-198 Denial Rate

Tracks claims denied because authorization limits were exceeded.

Unit Exhaustion Rate

Measures how often authorization reaches zero before planned treatment ends.

Reauthorization Lead Time

Measures how early requests are submitted before exhaustion.

Retro Authorization Rate

Shows how often practices depend on post-service approval.

Authorization Appeal Success Rate

Measures recovery after authorization denials. Follow us on LinkedIn to get more information.

Lost Revenue From Authorization Denials

Tracks unrecovered financial impact.

Unit Reconciliation Variance

Measures difference between internal units and payer-counted units.

Authorization Expiration Risk

Shows patients approaching date or quantity limits.

Build an Authorization Dashboard

A useful dashboard may include:

Patient
Payer
Authorization number
Service
Approved units
Used units
Remaining units
Utilization percentage
Expiration date
Estimated exhaustion date
Reauthorization status
Next appointment
Risk level

The dashboard should allow staff to quickly identify patients who need action.

Create a High-Risk Authorization Work Queue

Examples:

90%+ units used

Authorization expires within 10 days

Reauthorization pending

Zero units remaining

Payer/practice unit mismatch

New dose

New frequency

Insurance changed

Duplicate-claim review required

These work queues make authorization management proactive.

Why Therapy and Infusion Practices Need Different Controls

The same authorization system cannot always be used identically across specialties.

Therapy

Focus on:

Visits
Timed units
CPT pools
Frequency
Plan of care
Functional progress

Infusion

Focus on:

Drug units
Dose
J-code
Frequency
Administration
Site of care
Medication changes

The underlying principle is the same, but the operational details are different.

How PROMBS Helps Prevent Authorization-Related Revenue Loss

PROMBS supports medical practices with authorization and revenue-cycle workflows designed to prevent avoidable denials.

Prior Authorization Tracking

Authorization information can be monitored across:

Dates
Units
Visits
CPT/HCPCS
Providers
Payers

Unit Reconciliation

We help compare internal utilization against payer-side adjudication to identify discrepancies before they create larger denial patterns.

Reauthorization Follow-Up

Upcoming exhaustion points can be monitored so additional approval can be requested before treatment exceeds the current authorization.

Eligibility Verification

Coverage changes can be identified before outdated authorization information is used.

Therapy Billing Support

For therapy practices, PROMBS can support unit tracking, coding alignment, authorization monitoring, and denial follow-up.

Infusion Billing Support

For infusion practices, PROMBS can help reconcile drug units, J-codes, administration services, authorization quantities, and payer rules.

Denial Management

When authorization denials occur, our team can investigate the root cause, review payer utilization, correct claim issues, and support appeals where appropriate.

Revenue Cycle Analytics

Authorization trends can be reviewed by payer, specialty, provider, denial code, and root cause to identify recurring revenue leakage.

Frequently Asked Questions

What does “authorization units exhausted” mean?

It means the payer believes the approved quantity of units, visits, treatments, or services has already been used.

Can authorization still be active if units are exhausted?

Yes. The authorization end date may still be in the future even though the approved quantity has already been consumed.

What is CO-198?

CO-198 generally indicates that an authorization, notification, or precertification limit was exceeded.

What is the difference between CO-197 and CO-198?

CO-197 generally involves missing authorization. CO-198 generally means authorization existed but the approved limit was exceeded.

Can therapy visits continue after authorized units run out?

Clinically, treatment may still be needed, but reimbursement may be at risk unless additional authorization is obtained according to payer requirements.

How early should reauthorization begin?

It should begin early enough to account for payer processing time and the patient’s current utilization rate. Practices should use remaining units and burn rate rather than waiting until the final visit.

Can duplicate claims consume authorization units?

Yes. Depending on payer processing, duplicate or corrected claims can temporarily affect utilization counts and create discrepancies.

Can infusion dose changes affect authorization?

Yes. A higher dose may consume drug authorization units faster and may require additional approval.

Can a CO-198 denial be appealed?

Yes, when documentation supports the appeal, particularly if payer unit counts are incorrect, valid authorization was not applied, or medical necessity and payer rules support additional review.

Final Takeaway

Authorization management is not complete when an approval number is obtained.

The real work is keeping the authorization aligned with the patient’s actual treatment.

For therapy and infusion practices, the safest workflow is:

Authorize → track → reconcile → forecast → reauthorize → verify → bill

The most important numbers are not just the approved units.

Practices should continuously understand:

What was authorized

What was scheduled

What was delivered

What was billed

What the payer counted

What remains

When these numbers stay aligned, practices can prevent many authorization units exhausted denials before they happen.

PROMBS can help practices strengthen prior authorization tracking, therapy and infusion billing, unit reconciliation, denial management, and reauthorization workflows so medically necessary treatment is less likely to become preventable revenue loss.