ICD-10 Code R11.2: Nausea with Vomiting, Unspecified

Key Takeaways

R11.2 is a valid, billable ICD-10-CM code for nausea with vomiting when no specific cause has been identified.

The inclusion term is ‘Persistent nausea with vomiting NOS’ – use R11.2 only when both symptoms are present simultaneously.

Postoperative vomiting (K91.0) is explicitly excluded from R11.2; always verify the exclusion before coding.

Pabau’s claims management software helps reduce R11.2 claim denials by flagging exclusion conflicts and supporting accurate diagnosis documentation.

Claim denials for nausea and vomiting codes are more common than many billing teams expect. The R11 category contains nine distinct codes, and selecting the wrong one – particularly using R11.2 when only one symptom is present – is one of the most frequent causes of avoidable rejections. Claims management software that flags these distinctions at the point of documentation can prevent downstream billing errors before they reach the payer.

ICD-10 Code R11.2: Definition and Billable Status

ICD-10 Code R11.2 is a valid, billable ICD-10-CM diagnosis code for Nausea with vomiting, unspecified. It is valid for dates of service on or after October 1, 2015, when CMS mandated the transition from ICD-9-CM to ICD-10-CM for all HIPAA-covered entities. The code sits within Chapter 18 of the ICD-10-CM tabular list, which covers symptoms, signs, and abnormal clinical and laboratory findings not elsewhere classified (R00-R99), under the subcategory R10-R19 (Symptoms and signs involving the digestive system and abdomen).

The single inclusion term for R11.2 is Persistent nausea with vomiting NOS. “NOS” stands for “not otherwise specified,” confirming that this code applies when documentation captures both nausea and vomiting but does not specify an underlying cause, a specific vomiting pattern, or a more precise clinical classification. ICD-10-CM diagnostic codes in Chapter 18 are by design symptom-level codes used when a definitive diagnosis has not yet been established or cannot be more precisely coded.

R11.2 and Related Nausea and Vomiting Codes

The R11 category includes nine codes covering distinct clinical presentations. The most consequential coding decision involves distinguishing R11.2 from the other R11 codes – selecting the wrong code based on documentation that actually supports a more specific choice is a routine audit finding. According to the ICD-10-CM Official Guidelines for Coding and Reporting published by CMS and the National Center for Health Statistics (NCHS), coders should always assign the most specific code supported by the documented clinical information.

• R11.0 – Nausea only: Use when the patient has nausea without vomiting. Never assign R11.2 when vomiting is absent from the clinical note.
• R11.10 – Vomiting, unspecified: Vomiting without nausea documented; cause unspecified.
• R11.11 – Vomiting without nausea: Patient is vomiting but explicitly denies nausea, or nausea is not documented.
• R11.12 – Projectile vomiting: Use when the clinician specifically documents projectile vomiting as a distinct clinical feature.
• R11.13 – Vomiting of fecal matter: Rare presentation; requires explicit documentation of feculent vomitus.
• R11.14 – Bilious vomiting: Documentation must confirm bile-stained emesis.
• R11.15 – Cyclical vomiting syndrome unrelated to migraine: Distinct clinical entity; requires pattern documentation and ruling out migraine association.
• R11.16 – Cannabis hyperemesis syndrome: Use when the patient presents with the characteristic CHS triad (cyclic vomiting, abdominal pain, compulsive hot bathing) in the context of chronic cannabis use. Documentation must establish the cannabis use connection and rule out other cyclical vomiting causes.
• R11.2 – Nausea with vomiting, unspecified: Both symptoms present; no specific cause, pattern, or variant documented.

The critical rule: R11.2 requires both nausea and vomiting to be documented. If only one symptom appears in the clinical note, a different code from the R11 category applies. Coders relying on a related ICD-10-CM symptom codes reference should verify which symptom combination each code describes before assignment.

Exclusion Notes and When Not to Use ICD-10 Code R11.2

The R11 category carries a Type 2 Excludes note for K91.0 – Vomiting following gastrointestinal surgery. A Type 2 Excludes note means the excluded condition is not part of R11.2 but can be coded separately when both conditions are genuinely present. In practice, this means coders should not use R11.2 as the primary code for postoperative vomiting – K91.0 is the appropriate code for that clinical scenario. Misassigning R11.2 to surgical recovery nausea is a common documentation error in ambulatory surgical settings. Clinical documentation workflows that capture the postoperative context at intake prevent this misclassification.

Several other common clinical scenarios require codes from entirely different chapters rather than R11.2:

• Pregnancy-related nausea and vomiting: When nausea and vomiting occur in the context of pregnancy, codes from the O21 category (hyperemesis gravidarum) apply. R11.2 is not appropriate for obstetric patients when the pregnancy is the underlying cause. The ICD-10-CM Official Guidelines are explicit: symptoms integral to a confirmed condition are not coded separately.
• Chemotherapy-induced nausea and vomiting (CINV): While some reference sources list CINV as a synonym for R11.2, more specific adverse effect codes from the T45.1x- category may apply depending on payer requirements. Verify with the payer’s LCD before defaulting to R11.2 for oncology patients.
• Postoperative nausea and vomiting (PONV): As noted above, K91.0 is the appropriate code. Using R11.2 for PONV will frequently trigger payer edits.

ICD-10 Code R11.2 MS-DRG Groupings and Billing Context

Under MS-DRG version 43.0, ICD-10 Code R11.2 groups to two Medicare Severity Diagnosis Related Groups when submitted as a principal or secondary diagnosis on inpatient claims:

• MS-DRG 391: Esophagitis, gastroenteritis and miscellaneous digestive disorders with MCC (Major Complication or Comorbidity)
• MS-DRG 392: Esophagitis, gastroenteritis and miscellaneous digestive disorders without MCC

The presence or absence of a major complication or comorbidity in the patient’s record determines which DRG is assigned, with MS-DRG 391 commanding a higher relative weight and corresponding higher reimbursement. Billing teams at GP and primary care clinics submitting inpatient R11.2 claims should ensure all documented comorbidities are captured in the coding – an undercoded comorbidity directly reduces the DRG weight. For outpatient claims, R11.2 is used as a standalone diagnosis code without DRG grouping, supporting medical necessity for office visits, antiemetic prescriptions, or further diagnostic workup.

The ICD-9-CM crosswalk for R11.2 is 787.01 (Nausea with vomiting), a direct one-to-one conversion confirmed by ICD List and CMS conversion tools. Practices that retained legacy billing records from pre-2015 encounters should reference 787.01 when reconciling historical claims or appeals.

Clinical Documentation Requirements for R11.2

Supporting documentation for R11.2 must clearly establish three elements: the presence of nausea, the presence of vomiting, and the absence of a more specific confirmed diagnosis or etiology. Incomplete documentation – particularly a note that mentions vomiting without explicitly confirming associated nausea, or vice versa – is the primary trigger for medical necessity denials on R11.2 claims. HIPAA-compliant documentation practices require that the clinical record independently supports every code submitted on the claim.

Recommended documentation elements for R11.2 encounters:

• Explicit mention of both nausea and vomiting in the subjective or objective section of the note
• Onset, duration, frequency, and severity of symptoms
• Relevant negatives: absence of blood in vomitus, no feculent character, no documented projectile pattern
• Any diagnostic workup ordered to rule out a specific etiology (lab work, imaging, endoscopy referral)
• Treatment provided: antiemetic medication prescribed or administered, IV fluid status, dietary modification
• Context ruling out obstetric or postoperative cause, where relevant

Practices using a patient record system with structured note templates can build these documentation checkpoints directly into the encounter workflow. Structured intake and charting templates reduce reliance on free-text documentation, which is more susceptible to gaps during claim review. Digital intake forms that capture symptom onset, duration, and associated features create an auditable documentation trail from the patient’s first interaction with the practice.

Common Claim Denial Patterns and How to Avoid Them

Denials involving R11.2 typically fall into four categories. Understanding each one reduces rework and accelerates reimbursement cycles. The AAPC and payer LCD policies are the authoritative sources for claim edit logic on diagnosis codes in the R11 range.

Practices seeing recurring R11.2 denials should audit the documentation at the point of note completion rather than at the billing stage. Catching a missing “associated nausea” phrase before the note is finalized costs minutes – catching it after a denial costs days or weeks in rework and appeals. Symptom-based ICD-10-CM codes across Chapter 18 share this documentation challenge: the code is defensible only when the note explicitly supports it.

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ICD-9 to ICD-10 Crosswalk and Code History

ICD-10 Code R11.2 replaced ICD-9-CM code 787.01 (Nausea with vomiting) on October 1, 2015, as part of the mandatory US transition to ICD-10-CM. The crosswalk is a direct one-to-one conversion with no ambiguity – 787.01 maps exclusively to R11.2, and R11.2 maps back to 787.01 only. Practices handling retrospective audits, payer appeals, or coordination of benefits for encounters prior to FY2016 should use 787.01 for any date of service before October 1, 2015.

The WHO’s ICD-10 browser classifies the equivalent code in the international ICD-10 system under the same conceptual category (R11, Nausea and vomiting), though the US ICD-10-CM edition maintained by CMS and NCHS includes additional specificity codes not present in the WHO international version. All US payers require the ICD-10-CM edition. The current edition in effect is FY2026, effective October 1, 2025.

Expert Picks

Need to document GI symptoms accurately across your practice? Pabau Claims Management Software supports accurate diagnosis capture and pre-submission claim editing to reduce R11.2 denials.

Managing symptom documentation for multiple clinic locations? Digital Forms allows you to build structured intake templates that capture the symptom detail required to support ICD-10-CM codes at audit.

Looking for a broader guide to ICD-10-CM symptom codes? Situational Anxiety ICD-10 Code covers how to apply Chapter 18 symptom-level codes correctly when a definitive diagnosis is pending.

Conclusion

ICD-10 Code R11.2 is straightforward in concept but precise in application. Both symptoms must be documented, the clinical context must rule out postoperative, obstetric, and other excluded causes, and the documentation must not support a more specific R11 sub-code. Those three conditions determine whether R11.2 is defensible on a claim.

Pabau’s claims management software and structured clinical documentation tools help practices capture symptom-level detail at the point of care, reducing the documentation gaps that trigger R11.2 denials. To see how Pabau supports accurate diagnosis coding across your practice workflows, book a demo.

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