Altered Mental Status ICD-10 Code R41.82: 2026 Provider Guide

This guide is based on the FY 2026 ICD-10-CM code set and Official Guidelines applicable through September 30, 2026. Code selection depends on the provider's documentation, encounter setting, and current Index and Tabular instructions.

R41.82 is the ICD-10-CM code for altered mental status, unspecified, reported when that diagnosis matches what the provider documented and no more definitive condition appears on the chart. A more definitive diagnosis calls for a different code, and the right choice still depends on the encounter setting and current coding instructions.

Search habits vary, but they land in the same place. AMS ICD-10, altered mental status ICD-10, the ICD-10 code for AMS, the ICD-10 AMS shorthand: all four point to R41.82.

In the Alphabetic Index, this presentation is filed as an ICD-10 change in mental status entry, cross-referenced to Change in mental status NOS. That entry is the altered mental status ICD-10 code most billing teams already use, so it also answers the ICD-10 code for altered mental status search.

The table below lays out the core facts coders need before touching a claim.

A billable code isn't the same as a paid claim, and that gap shows up again later in this guide. This guide covers when the code applies, how it differs from confusion and altered awareness, where delirium and encephalopathy fit, and what changes between inpatient, outpatient, and claim documentation.

What Does R41.82 Mean in ICD-10-CM?

R41.82 Code Facts for FY 2026

R41.82 describes altered mental status, unspecified, inside the R41 category for symptoms and signs involving cognitive functions and awareness. It's a symptom code, not a diagnosis, and it's billable at the level shown here.

"Change in mental status NOS" is the applicable term coders will see in the Alphabetic Index, and an ICD-10 altered mental status search in that Index lands on this same entry.

The Index doesn't care how you type it. AMS ICD-10, ICD-10 code AMS, ICD-10 change in mental status, altered mental status ICD10 with no hyphen: all of it routes to R41.82. That FY 2026 status runs from October 1, 2025 through September 30, 2026, per the CMS ICD-10 files.

What "Unspecified" Means

"Unspecified" describes the level of diagnostic detail in the documentation, not the quality of the code itself. It does not mean the code is invalid, that the claim will be denied on sight, or that a coder can infer a more specific diagnosis the provider never wrote down.

It also doesn't mean the workup was incomplete. The CDC ICD-10-CM files behind this code set are maintained through the National Center for Health Statistics, and they treat unspecified codes as a normal, supported part of the classification, not a fallback to avoid.

A penalty for reporting R41.82 as unspecified isn't built into the code itself. It shows up, if at all, through documentation gaps or payer-specific edits, covered later in this guide.

What R41.82 Does Not Establish

R41.82 alone does not establish delirium, encephalopathy, coma, or dementia. It doesn't name a cause for the mental status change, and it doesn't establish coverage for a service or set a reimbursement amount. Those all depend on separate documentation, separate codes, and separate payer rules.

Coders searching the ICD-10 code for altered mental status sometimes expect one code to answer every question on a chart. This one only answers the question the provider documented, nothing more.

When Is R41.82 Appropriate for Altered Mental Status?

When No Definitive Diagnosis Has Been Established

R41.82 may be appropriate when the provider documents altered mental status and the record doesn't yet support a more definitive diagnosis for that encounter. That's the entire test behind any ICD-10 code for altered mental status decision: does the chart go further than "altered," or not?

The documentation has to support the symptom itself, not imply it, and nothing in the Tabular List should point the coder elsewhere first. Reported this way, R41.82 represents the highest level of certainty the record supports, not a placeholder to hold until more tests come back.

A workup can stay open and the code can still be correct, as long as what's documented matches what's reported. Whether the search that led here was for the ICD-10 code for AMS, an ICD-10 altered mental status question, or a plain altered mental status ICD-10 lookup, the standard doesn't change: report what the chart shows.

Why Unspecified Does Not Mean Incorrect

Official coding guidance recognizes real, supported uses for unspecified codes; they aren't a lesser category to apologize for. The FY 2026 ICD-10-CM Official Guidelines treat signs, symptoms, and unspecified codes as acceptable whenever they accurately reflect what's documented, whether that search started as an ICD-10 AMS question or an ICD-10 change in mental status question.

The correct code is the one the record supports. Chasing specificity the documentation doesn't back up isn't better coding, it's a compliance risk. A coder can't convert altered mental status into delirium or encephalopathy because a patient is elderly, agitated, or septic; that call belongs to the provider, not the claim.

A definitive diagnosis shouldn't get chosen because it pays differently, either. When coding uncertainty like this keeps creating pre-submission edits or bounced claims, MedSole's claims submission services can review whether the diagnosis reporting, documentation, and payer-specific requirements line up before anything goes out the door.

When Another Code Should Be Reviewed

Another code family deserves a look once the provider documents something more specific than what R41.82 covers: disorientation, transient altered awareness, somnolence, stupor, coma, delirium, encephalopathy, intoxication or withdrawal, stroke, or another definitive condition. None of that gets decided from clinical indicators alone, and the comparisons in the next few sections walk through exactly where each documented presentation points.

What Is Altered Mental Status?

A Change From the Patient's Baseline

Altered mental status is a broad clinical description, not a single diagnosis. It covers an unexpected change from a patient's baseline in one or more areas: awareness, attention, cognition, orientation, responsiveness, or behavior.

That framing tracks with the NIH altered mental status review of the topic, which describes it as a nonspecific shift away from a patient's usual level of awareness, thinking, focus, or alertness rather than a stand-alone diagnosis.

Two patients can carry the same AMS ICD-10 label and look completely different at the bedside. One might be quietly inattentive; another might be agitated and combative. Both fit the same broad description.

Common Documented Presentations

Providers document altered mental status through a handful of recurring presentations:

• Acute confusion
• Disorientation
• Inattention
• Memory change
• Agitation
• Unusual behavior
• Reduced responsiveness

Not every one of these maps to R41.82 on its own. The presentation is clinical context, not a coding rule; the diagnosis the provider writes down still drives the code. A nursing note that says "confused" and a physician's final assessment don't carry the same coding weight.

Why the Clinical Cause Still Matters

Altered mental status can show up alongside infection, a metabolic disturbance, medication effects, substance use, a neurological event, organ dysfunction, or trauma. The presentation looks similar on the chart from one patient to the next; the cause underneath rarely is.

A sudden change in mental status can signal a medical emergency in progress. It calls for prompt evaluation, not a wait-and-see approach, and that clinical urgency sits entirely outside what any diagnosis code can capture on its own.

Which ICD-10-CM Code Fits the Documented Mental-Status Change?

R41.82 and Related ICD-10-CM Codes

R41.82 shares a neighborhood with several related codes, each describing a different documented presentation. Some searches for the ICD-10 code for altered mental status, an ICD-10 altered mental status question, or the exact altered mental status ICD-10 code end up needing R41.0, R40.4, F05, or one of the encephalopathy codes instead.

The table below is a navigation tool, not a substitute for reading the complete Index and Tabular entries.

How to Use the Table

Work through it in order, not by symptom alone:

• Start with the provider's final diagnostic statement.
• Identify whether the documentation describes cognition, orientation, awareness, or consciousness.
• Review the Alphabetic Index.
• Confirm the Tabular List.
• Apply setting-specific rules for the encounter.

The CDC ICD-10-CM Browser makes the Index and Tabular checks fast when a coder needs to confirm a code on the spot.

That same discipline applies no matter which query brought a coder here, whether it was AMS ICD-10, confusion ICD-10, the ICD-10 code for AMS, or the ICD-10 code AMS shorthand: verify the Index before assuming the answer.

Do not infer a diagnosis from clinical indicators alone. A lab value or a nursing note is not the same as a documented diagnosis.

What the Table Does Not Do

The table simplifies a real decision, and simplification has limits:

• It does not replace the complete code set.
• It does not establish medical necessity.
• It does not guarantee reimbursement.
• It does not authorize a coder to diagnose anything the provider didn't.
• It does not resolve conflicting documentation.

When the choice between R41.82 and a neighboring code still isn't clear after checking the Index, the Tabular List, and the encounter notes, that's a signal for a compliant provider query, not a coder's best guess.

R41.82 vs R41.0: Altered Mental Status and Disorientation

The Practical Difference

R41.82 and R41.0 are not interchangeable. The first represents altered mental status, unspecified; the second represents disorientation, unspecified, with confusion NOS listed as an alternate term. The right choice depends on the provider's documented diagnostic statement, not on which word landed on the chart.

Picking the broader code out of habit, or the narrower one because it sounds more precise, creates a pattern a payer audit can flag later, even when any single claim looks fine on its own.

When Documentation Supports R41.0

R41.0 may be the code to review when the provider documents disorientation, confusion NOS, or a disturbance involving person, place, time, or situation.

Not every use of the word "confused" automatically supports a disorientation ICD-10 diagnosis, and a plain confusion ICD-10 search doesn't settle the question on its own. A nursing note that says a patient seems confused is an observation, not a diagnosis.

The documentation has to establish what the provider is diagnosing before this code becomes the answer. A physician's own assessment carries that weight; a triage note by itself usually doesn't.

When Documentation Supports R41.82

The broader, unspecified option tends to fit better when the record describes a wide mental status change that isn't limited to disorientation alone. When the provider's language stays general, altered mental status ICD-10 reporting through the R41 category usually holds up better than forcing the chart into a narrower confusion ICD-10 or disorientation ICD-10 code it doesn't quite support.

Documentation Examples

These examples show documentation logic, not a universal coding outcome. Two similar-sounding charts can point to two different codes once the actual wording gets read line by line, which is exactly why the provider's own words matter more than the coder's first impression.

R41.82 vs R40.4: Altered Mental Status, Awareness, and Consciousness

R40.4 Describes Transient Alteration of Awareness

Transient alteration of awareness ICD-10 reporting means R40.4, and it shouldn't become the default choice for every undifferentiated altered mental status ICD-10 encounter because the two codes sit close together in the Tabular List.

R41.82 covers a broad, unspecified mental-status change. R40.4 covers a temporary shift in awareness specifically, and the provider's own terminology decides which direction fits, not how long the episode lasted.

A note that reads "briefly unaware of surroundings after the seizure resolved" points toward R40.4. A note that reads "mental status remains altered, cause unclear" points toward the broader code instead, since nothing in it describes a resolved, time-limited episode.

Altered Awareness Is Not the Same as Reduced Consciousness

Awareness, attention, cognition, orientation, arousal, responsiveness, and consciousness overlap, but they aren't identical on a chart. A patient can be fully awake and oriented yet inattentive, which points toward one presentation.

A patient who won't rouse at all points toward another. An altered level of consciousness ICD-10 question usually signals that second pattern, not the first, and mixing the two up in a query can send a provider chasing the wrong clarification.

Somnolence, Stupor, Coma, and Unresponsiveness

Reduced arousal or responsiveness tends to direct the coder toward the R40 family rather than the broader unspecified code. That family runs from full alertness down to coma, and it covers somnolence ICD-10 territory, stupor, coma, and unresponsiveness ICD-10 territory alike, plus transient alteration of awareness ICD-10 again when the change is brief and resolves on its own.

No single symptom assigns a code by itself. A drowsy patient and an unrousable one sit at opposite ends of the same category, and the documented condition, not the bedside impression, decides which specific code applies.

Excludes1 Direction

In plain terms, altered level of consciousness ICD-10 territory under R40.- stays separate from altered mental status, unspecified, under the same coding instruction. A coder can't report both for the same presentation at the same time.

That Excludes1 direction is a formatting rule built into the Tabular List, not a judgment call, and Part 2 of this guide covers the full mechanics behind R40.4 and its neighbors in the R40 category.

For now, the working rule holds: report the level of consciousness if the provider documented one, and reach for the broader code only when nothing more specific is on the chart.

R41.82 vs Delirium and Encephalopathy

Altered Mental Status Is Not Automatically Delirium

Altered mental status and delirium are not the same thing. Altered mental status is a broad symptom description, while delirium is a narrower clinical diagnosis marked by a specific, usually fluctuating pattern of inattention and disturbed awareness. F05 covers delirium due to a known physiological condition, and reporting it requires the provider to name that condition, not describe confusion or agitation alone.

A coder can't infer delirium from confusion, agitation, or age alone; those are clinical indicators, not a diagnosis. When a provider documents delirium without a known physiological cause attached, that presentation often routes to R41.0 instead of F05, since F05 requires a documented condition behind it. That connection has to come from the provider, not the coder.

Altered Mental Status Is Not Automatically Encephalopathy

Altered mental status and encephalopathy aren't automatically the same either. Encephalopathy is a provider-documented diagnosis, not a label a coder assigns from lab results. G93.40 covers encephalopathy, unspecified, while G93.41 covers metabolic encephalopathy specifically, and altered mental status plus infection, abnormal labs, or organ dysfunction doesn't establish either one without the provider's own diagnostic statement.

Clinical indicators like fever, an abnormal ammonia level, or an elevated white count may support a compliant clarification query. They don't let a coder create the diagnosis on the provider's behalf. A UTI with confusion doesn't automatically become G93.40 on a coder's own judgment, and abnormal labs alone don't establish G93.41 without a provider naming it.

Do Not Chase a Higher-Weight Diagnosis

Altered mental status ICD-10 reporting, like every other diagnosis on the claim, can't be driven by expected reimbursement. The record has to support whatever gets reported, whether that's the broader unspecified code, a specific encephalopathy diagnosis, or nothing more definitive than what's already on the chart.

Documentation improvement should clarify the patient's actual condition, not steer a provider toward whichever label pays more. A compliant query stays non-leading: it presents clinical indicators and asks the provider to specify, and it never suggests G93.41 metabolic encephalopathy, or any other diagnosis, as the preferred answer.

Some of these diagnoses affect claim weighting more than others once they're confirmed, which is why a leading query creates a compliance problem beyond the paperwork. Part 2 of this guide covers that reimbursement impact directly.

When the same documentation gaps keep resurfacing from coding straight through to claim edits and denials, MedSole's revenue cycle management services can look at the full workflow instead of treating each one as a separate event.

Side-by-Side Documentation Matrix

Each row starts with what the provider wrote, not what the presentation might suggest. That order matters more here than almost anywhere else in this guide.

How Do Inpatient, Outpatient, ED, and Observation Rules Change AMS Coding?

Inpatient Coding at Discharge

In an inpatient encounter, altered mental status ICD-10 reporting follows the condition established after study as chiefly responsible for the admission, based on discharge documentation rather than the admission complaint. A symptom can still serve as principal diagnosis when no definitive condition is established after study and the symptom chiefly occasioned the admission.

Qualifying uncertain diagnoses, language like probable, suspected, likely, questionable, possible, or still to be ruled out, may be coded as though established at discharge in an applicable inpatient setting.

Initial documentation of R41.82 doesn't automatically stay the principal diagnosis once a definitive condition is established later in the stay. Conflicting diagnostic statements in the record are a signal for clarification, not a coder's judgment call.

Outpatient and Emergency Department Coding

In an outpatient or ED encounter, AMS ICD-10 coding follows the highest degree of certainty known at the end of the visit, and that standard applies to physician offices, hospital outpatient departments, emergency departments, and observation services alike. Probable, suspected, questionable, or rule-out diagnoses don't get coded as established here the way they can at inpatient discharge.

Report the confirmed condition when one exists. When no definitive diagnosis is established, report the supported signs, symptoms, abnormal findings, or reason for the encounter instead.

R41.82 may be first-listed when it accurately represents the final documented condition, and official guidance points coders toward the highest certainty available rather than treating an uncertain diagnosis as confirmed. That's the standard behind any ICD-10 altered mental status question in the ED.

Observation Is Outpatient

Observation status does not use the inpatient uncertain-diagnosis rule. A patient can occupy a hospital bed overnight and still count as an outpatient for diagnosis-coding purposes, since observation runs under outpatient rules regardless of stay length.

Documentation Timing Matters

A presenting complaint, an initial impression, a differential diagnosis, a working diagnosis, a final assessment, and an inpatient discharge diagnosis are six different documents that can carry six different levels of certainty.

The coding outcome follows whichever document applies to the setting and stage of care, not whichever one came first. R41.82 fits some of these and not others.

Can R41.82 Be Principal or First-Listed?

Yes, R41.82 may be principal or first-listed, but the setting changes the rule that applies. Inpatient principal-diagnosis selection asks what was established after study as chiefly responsible for the admission.

Outpatient first-listed selection asks what was confirmed, or what remains the best-supported reason for the visit, by the end of the encounter. Either way, no more definitive diagnosis can have replaced the symptom on the record, and documentation plus current Index and Tabular instructions control the result.

R41.82 as an Inpatient Principal Diagnosis

Altered mental status ICD-10 selection as an inpatient principal diagnosis depends on whether AMS is the condition established after study as chiefly responsible for the admission, with no definitive diagnosis replacing it.

That decision for R41.82 rests on the circumstances of admission, the final provider documentation, the condition established after study, and the current Index and Tabular instructions together, not any single factor alone.

The code isn't automatically principal because altered mental status showed up in the chief complaint. The discharge record has to still support it once the workup is finished.

R41.82 as an Outpatient First-Listed Diagnosis

The same code may be first-listed when it represents the reason for the encounter, the highest degree of certainty established, and the provider's final documented diagnosis. It also works as a supported symptom when no definitive condition is confirmed by the end of the visit.

What Happens When a Definitive Diagnosis Is Established?

Report the definitive diagnosis once it explains the encounter. Symptoms routinely associated with that diagnosis generally aren't coded separately, though a symptom that isn't routinely associated may still be reportable when the documentation supports it.

There's no universal "cause first, AMS second" formula here. Code-specific sequencing instructions govern when they apply, and an ICD-10 change in mental status entry doesn't override an instruction that says otherwise.

How the Excludes1 Note Affects R41.82

An Excludes1 note generally means "not coded here." The excluded condition shouldn't be reported alongside the code above the note, apart from a limited case where the two conditions are documented as unrelated.

For this code, altered level of consciousness under R40.-, including R40.4, AMS due to a known condition, and delirium NOS under R41.0 each need their own coding direction, not a blanket combination with the broader unspecified code or with G93.41.

What Documentation Supports R41.82?

Establish the Patient's Baseline

Documentation that supports R41.82 starts with the patient's normal cognitive or mental status and where that baseline came from, whether that's family, a caregiver, EMS, or prior records.

The record should also say whether the change is new, chronic, or acute on top of a chronic condition. None of this means a provider should add language they didn't clinically observe; it means the baseline that was observed belongs on the chart. An altered mental status ICD-10 code is only as strong as the baseline behind it.

Describe the Current Change

The current presentation deserves its own documented findings: onset and duration, an acute, chronic, or fluctuating course, orientation, attention, memory, behavior, responsiveness, speech, functional change, and any associated neurological or systemic findings.

These are objective findings, separate from the final diagnostic statement. A chart can be full of clinical detail and still lack the one sentence a coder needs. Documentation that only says a patient seems confused, without a provider diagnosis attached, supports a confusion ICD-10 or disorientation ICD-10 lookup better than it supports a billable claim.

Document the Diagnostic Conclusion

The provider's final assessment should say plainly whether the conclusion is altered mental status, unspecified, disorientation, transient alteration of awareness, delirium, encephalopathy, intoxication or withdrawal, a neurological diagnosis, or another documented cause.

A checklist can prompt a provider to document more completely, but it can't create a diagnosis. Only the provider's own clinical judgment separates R41.82 from R41.0, and only their documentation can make that separation clear on the record.

Update the Final Record

The final assessment and discharge summary should reconcile the initial complaint, the workup, what got ruled in or ruled out, the final diagnosis, cause-and-effect wording, and whether the mental-status change resolved or stayed unexplained. The table below maps each documentation element to the reason a coding team needs it.

When Should a Documentation Clarification Be Considered?

A coder should consider a clarification when altered mental status ICD-10 documentation is inconsistent, incomplete, ambiguous, or conflicting, not because a claim got denied or a diagnosis would pay differently. The goal is a complete, accurate record, and reimbursement pressure has no place in that decision.

Documentation Patterns That May Need Clarification

A handful of patterns tend to justify a closer look: R41.82-type language appearing throughout the record with no final diagnosis ever recorded, delirium and encephalopathy used interchangeably, a documented diagnosis that conflicts with other provider statements, and a possible cause discussed without a stated relationship.

The same is true for acute confusion documented on top of baseline dementia, a final assessment that conflicts with the discharge summary, a diagnosis appearing only in non-provider documentation when provider confirmation is required, and clinical indicators that don't line up with the documented diagnosis.

What a Compliant Clarification Should Accomplish

A clarification should present the relevant clinical indicators, name the documentation issue, offer clinically reasonable choices when choices are used, include an "other" option, and permit an "unable to determine" response. It should never point a provider toward a financially favorable diagnosis, and it always has to preserve the provider's own independent clinical judgment.

What Not to Ask

A query shouldn't assume G93.40 or G93.41 encephalopathy from AMS plus abnormal lab values, suggest a diagnosis because it would count as an MCC, treat a payer denial as proof another diagnosis belongs on the chart, ask a provider to document something that was never clinically evaluated, or leave out clinical indicators that don't support the suggested answer.

The current ACDIS and AHIMA compliant query guidance remains the 2022 update with its 2023 addendum addressing denial trends. Coders and CDI teams should confirm they're working from the version currently published before building or revising query templates.

Does a Billable R41.82 Code Guarantee Payment?

R41.82 is a billable ICD-10-CM code, but billable does not mean guaranteed payable. Coders searching the ICD-10 code AMS or the ICD-10 AMS shorthand are usually asking a coding question, not a coverage question, though the two get merged more often than they should.

A code being valid at the required specificity says nothing about whether a specific payer will cover the visit, consider it medically necessary, or pay the claim. Those are four separate questions with four separate answers.

Four Terms That Should Not Be Treated as Synonyms

Mixing these terms up is where a lot of avoidable confusion starts, especially when a denial gets blamed on "the diagnosis code" when the real issue sits somewhere else in the claim.

Why a Valid Diagnosis Code Can Still Fail

Payment can still be affected by a diagnosis and procedure mismatch, missing documentation, service-specific coverage criteria, an incorrect setting or place of service, eligibility, prior authorization, timely filing, bundling and modifier rules, contract terms, or payer-specific edits.

None of that means altered mental status ICD-10 reporting has one universal reimbursement rate. It means the code is one input among many, and every one of those other inputs has to line up too.

How to Check Medicare Coverage

Practices can search the Medicare Coverage Database by diagnosis code, procedure code, keyword, NCD, LCD, or Billing and Coding Article. The database matches CPT or HCPCS services with diagnosis codes, and the relevant MAC articles and LCDs often spell out the coverage requirements behind a specific service.

Common R41.82 Claim Risks and Six Coding Scenarios

Claim Problems to Review

Six patterns show up again and again in claims built around the ICD-10 code for altered mental status, whether the original search was for the ICD-10 code for AMS or the full term:

1. R41.82 conflicts with the final provider diagnosis. 2. A more specific diagnosis was inferred rather than documented. 3. R41.82 is reported alongside an excluded or integral condition. 4. The outpatient claim reports a suspected diagnosis as though it were confirmed. 5. The service and the diagnosis don't satisfy payer requirements. 6. Initial and final documentation don't reconcile.

None of these are automatic denials. Depending on the payer and the service, each pattern may trigger a coding edit, a documentation request, a medical-necessity review, or a denial.

The fix looks different every time, which is exactly why treating every claim problem as the same issue rarely works.

When the same pattern keeps showing up as an edit or a denial, MedSole's denial management services can trace the failure back to coding, documentation, medical necessity, or payer policy instead of resubmitting the same claim and hoping for a different result. Claims already sitting unpaid past the initial denial are a separate problem that AR follow-up services are built to chase down.

Six Setting-Specific Scenarios

The setting almost always changes the answer, even when the presenting complaint reads the same on paper. The six scenarios below cover the situations that come up most often across ED, outpatient, observation, and inpatient documentation.

FY 2026 CC and MCC Accuracy Note

G93.40, encephalopathy unspecified, is classified as a CC under the current FY 2026 severity rules. G93.41, metabolic encephalopathy, is classified as an MCC, per the FY 2026 MS-DRG Version 43.1 severity list. Severity status should never drive unsupported diagnosis selection on any altered mental status ICD-10 claim; the documentation still has to establish the condition before either code applies, regardless of what it would do to the DRG weight.

What Changed for Altered Mental Status Coding in 2026?

FY 2026 Code-Set Status

The April 1, 2026 ICD-10-CM files apply to AMS coding for encounters from April 1, 2026 through September 30, 2026. FY 2027 ICD-10-CM code files are already available for encounters beginning October 1, 2026, though the FY 2027 Guidelines were still listed as not yet available at the time this guide was last checked.

This page needs a recheck against the CMS ICD-10 code updates before October 1, 2026, when the new fiscal year takes over. Whether a practice searches altered mental status ICD10 without the hyphen or spells it out in full, coding decisions made after that date should confirm the current file set before relying on anything written here.

Required Update Protocol

Every reviewed page should display its last reviewed date, the applicable code-set period, the date sources were last checked, a named coding reviewer, and the next scheduled review. A change log should follow whenever guidance changes in a way that affects the coding advice on the page, including this one.

MedSole Pricing and Service Context

Practices that need ongoing support across coding review, claim submission, payment posting, denials, and AR can use MedSole's outsourced medical billing services at the rate shown above.

Provider enrollment and credentialing are separate from AMS code selection, but practices can also use MedSole's provider credentialing services at the per-insurance rate shown above. Keeping that pricing in its own table avoids implying that credentialing has anything to do with how R41.82 gets selected.

MedSole pricing shown above reflects MedSole's own published rates, not an industry average.

Altered Mental Status ICD-10 FAQs

What is the ICD-10 code for altered mental status?

R41.82 is the official altered mental status ICD-10 code, described as altered mental status, unspecified. It covers a mental-status change with no more specific diagnosis on the chart, and the right code still depends on the documentation and the encounter setting behind it.

When should R41.82 be used?

It fits when the provider documents altered mental status and no definitive diagnosis has been established for that encounter. The code reflects the highest certainty the record supports, and current Index and Tabular instructions still apply before a coder finalizes it.

Is R41.82 billable?

Yes, it's billable at the required reporting level, the same as any other valid diagnosis code. Billable doesn't mean every service tied to it is automatically covered or payable. Medical necessity and the specific payer's own policy still apply on top of that.

Can R41.82 be a principal diagnosis?

Yes, potentially, though the setting decides how. Inpatient principal-diagnosis selection depends on the condition established after study as chiefly responsible for the admission. Outpatient first-listed selection depends instead on the final supported reason for the encounter.

Is altered mental status the same as confusion?

No. Altered mental status is the broader term. R41.0 represents disorientation, unspecified, which is a narrower cognitive presentation. The provider's own wording in the record, not the patient's presentation alone, determines which direction is correct.

What is the difference between R41.82 and R40.4?

One covers unspecified altered mental status. The other, R40.4, describes transient alteration of awareness specifically. They aren't interchangeable, and the documented concept, not the duration of the episode alone, decides which code applies.

Is altered mental status the same as delirium?

No. Altered mental status is broad; delirium is a formal clinical diagnosis with its own criteria. F05 may apply when delirium due to a known physiological condition is documented, with that underlying condition named on the chart.

Is altered mental status the same as encephalopathy?

No. Encephalopathy has to be documented by the provider, not assembled by a coder from lab values. Nobody should infer G93.40 or G93.41 from altered mental status plus abnormal clinical indicators alone; the diagnosis has to come from the chart.

What is the ICD-10 code for altered mental status after a fall?

There's no single universal code based only on "after a fall." Review whether the provider documents an injury, altered awareness, a concussion, loss of consciousness, or unspecified AMS. The setting and the final documented diagnosis control which code gets reported.

What documentation supports R41.82?

Baseline status, acuity, onset, orientation, attention, responsiveness, the final diagnostic statement, and whether a cause was identified or stayed unresolved. Complete documentation across each of those points supports the code far better than any single isolated note ever could.

What was the ICD-9 code for altered mental status?

The historical ICD-9-CM code was 780.97. U.S. HIPAA-covered diagnosis reporting transitioned to ICD-10-CM for services on or after October 1, 2015, and that older code hasn't been valid for billing purposes since that date.

When documentation, coding, claim submission, and denial follow-up keep breaking at different points along the way, MedSole RCM can review the full process and show your practice exactly where the revenue cycle is losing accuracy.