What is ICD-10 code E16.3?

E16.3 is the ICD-10-CM diagnosis code for Increased secretion of glucagon. The pancreas is producing too much glucagon, a hormone that raises blood sugar levels. It belongs to the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89). E16.3 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. E16.3 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. E16.3 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. E16.3 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

What is the V28 vs V24 difference for E16.3?

E16.3 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither model rewards E16.3 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

What should coders know when reporting E16.3?

Document whether this is associated with a glucagonoma (pancreatic tumor) or other underlying cause Consider if this is a secondary finding related to another endocrine disorder or malignancy

E16.3: Increased secretion of glucagon — ICD-10

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupE16.3Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Endocrine, nutritional and metabolic diseases (E00-E89) / Other disorders of glucose regulation and pancreatic internal secretion (E15-E16)

E16.3

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Increased secretion of glucagon

The pancreas is producing too much glucagon, a hormone that raises blood sugar levels.

Buddy Insight

E16.

CMS-HCC V28

Not risk-adjusted for this model/period.

RAF 0

CMS-HCC V24

Not risk-adjusted for this model/period.

RAF 0

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Not risk-adjusted for this model/period.

RAF 0

RXHCC

Mapped

HCC 66

Pancreatic Disease and Disorders

RAF 0.0

Code Trumping

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Compare selected patient codes to show trumped or trumps impact.

Code Book Path

Official

E16Other disorders of pancreatic internal secretion

E16.3Increased secretion of glucagon

Inclusion Terms

Official

Hyperplasia of pancreatic endocrine cells with glucagon excess

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for E16.3 in this effective period.

Related Child Codes

Official

E16.0Drug-induced hypoglycemia without coma

E16.1Other hypoglycemia

E16.2Hypoglycemia, unspecified

E16.4Increased secretion of gastrin

E16.8Other specified disorders of pancreatic internal secretion

Includes

Official

ICD-10-CM does not list Includes notes for E16.3 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for E16.3 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for E16.3 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for E16.3 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for E16.3 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Documentation must include the diagnosis of increased glucagon secretion with supporting laboratory evidence (elevated serum glucagon levels).

The underlying cause, typically a pancreatic neuroendocrine tumor, should be identified.

Imaging findings and clinical manifestations should be documented.

MEAT Support

HCC Buddy guidance

Documentation must include the diagnosis of increased glucagon secretion with supporting laboratory evidence (elevated serum glucagon levels).

The underlying cause, typically a pancreatic neuroendocrine tumor, should be identified.

Imaging findings and clinical manifestations should be documented.

Audit Caution

HCC Buddy guidance

This code captures the hormonal excess, not the tumor itself.

If a glucagonoma is present, code the neoplasm separately.

Elevated glucagon can also occur in critical illness or diabetes, but E16.3 is specifically for pathological hypersecretion.

Common Mistakes

HCC Buddy guidance

E16.4 (increased gastrin secretion) for gastrinomas

E16.8 (other disorders of pancreatic internal secretion) for unspecified pancreatic endocrine tumors

C25.4 (malignant neoplasm of endocrine pancreas) which should be coded additionally for glucagonoma.

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Is E16.3 an HCC code?

No. E16.3 is a billable ICD-10-CM code but does not map to any HCC category in V28, V24, ESRD, or RxHCC.

HCC Category Mapping

RxHCCHCC 66, Pancreatic Disease and Disorders

0.000

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

MEAT Criteria for E16.3

For E16.3to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed E16.3 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

E16.3 is the ICD-10-CM diagnosis code for increased secretion of glucagon. The pancreas is producing too much glucagon, a hormone that raises blood sugar levels. E16.3 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering other disorders of glucose regulation and pancreatic internal secretion (e15-e16).

E16.3 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This code has no V28 or V24 HCC mapping in the provided data. Despite the lack of direct risk adjustment impact, accurate coding supports clinical documentation and may contribute to severity of illness measures. Coders reviewing E16.3 should check whether additional documentation would support a more specific child code in the same hierarchy that does map to a payment HCC, capturing the correct specificity is the highest-impact RAF improvement available within accurate coding.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for E16.3 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Document whether this is associated with a glucagonoma (pancreatic tumor) or other underlying cause
•Consider if this is a secondary finding related to another endocrine disorder or malignancy

Clinical Significance

E16.3 identifies increased secretion of glucagon, a rare condition typically caused by glucagonoma (a neuroendocrine tumor of pancreatic alpha cells). The glucagonoma syndrome classically presents with necrolytic migratory erythema, diabetes mellitus, weight loss, anemia, and venous thromboembolism, representing a clinically significant paraneoplastic syndrome.

Documentation Requirements

✓Documentation must include the diagnosis of increased glucagon secretion with supporting laboratory evidence (elevated serum glucagon levels).
✓The underlying cause, typically a pancreatic neuroendocrine tumor, should be identified.
✓Imaging findings and clinical manifestations should be documented.

Commonly Confused Codes

•E16.4 (increased gastrin secretion) for gastrinomas
•E16.8 (other disorders of pancreatic internal secretion) for unspecified pancreatic endocrine tumors
•C25.4 (malignant neoplasm of endocrine pancreas) which should be coded additionally for glucagonoma.