Diabetes ICD-10 Codes: Complete Coding Guide (E08-E13)
- Jan 20, 2025
Diabetes mellitus is one of the most frequently coded conditions in healthcare. With over 320 diagnosis codes spanning categories E08 through E13, accurate diabetes coding requires understanding the type of diabetes, associated complications, and proper sequencing rules. This comprehensive guide covers everything medical coders need to know about ICD-10-CM diabetes codes.
Overview of Diabetes Coding in ICD-10-CM
ICD-10-CM organizes diabetes codes into six main categories based on the type and etiology of the condition:
| Category | Description | When to Use |
|---|---|---|
| E08 | Diabetes due to underlying condition | Diabetes secondary to another disease (e.g., pancreatitis, cystic fibrosis) |
| E09 | Drug or chemical induced diabetes | Diabetes caused by medications or toxic substances |
| E10 | Type 1 diabetes mellitus | Insulin-dependent, autoimmune diabetes |
| E11 | Type 2 diabetes mellitus | Most common form; insulin resistance |
| E12 | Malnutrition-related diabetes | Rare in developed countries (merged into E13) |
| E13 | Other specified diabetes mellitus | Post-pancreatectomy, postprocedural, and other specified types |
Key statistics:
- Total diabetes codes in ICD-10-CM: 323 codes
- Billable diabetes codes: 237 codes
- Most commonly used: E11 (Type 2 diabetes mellitus)
Type 2 Diabetes Mellitus (E11) - Most Common
Type 2 diabetes accounts for approximately 90-95% of diabetes cases. The E11 category includes 48 billable codes organized by complication type.
E11 Code Structure
| 4th Character | Complication Type | Example |
|---|---|---|
| .0 | Hyperosmolarity | E11.00, E11.01 |
| .1 | Ketoacidosis | E11.10, E11.11 |
| .2 | Kidney complications | E11.21, E11.22, E11.29 |
| .3 | Ophthalmic complications | E11.31x through E11.37 |
| .4 | Neurological complications | E11.40 through E11.49 |
| .5 | Circulatory complications | E11.51, E11.52, E11.59 |
| .6 | Other specified complications | E11.61x through E11.69 |
| .8 | Unspecified complications | E11.8 |
| .9 | Without complications | E11.9 |
| .A | In remission | E11.A |
Common E11 Billable Codes
Most frequently used Type 2 diabetes codes:
- E11.9 - Type 2 diabetes mellitus without complications
- E11.65 - Type 2 diabetes mellitus with hyperglycemia
- E11.22 - Type 2 diabetes mellitus with diabetic chronic kidney disease
- E11.40 - Type 2 diabetes mellitus with diabetic neuropathy, unspecified
- E11.42 - Type 2 diabetes mellitus with diabetic polyneuropathy
- E11.319 - Type 2 diabetes mellitus with unspecified diabetic retinopathy without macular edema
- E11.621 - Type 2 diabetes mellitus with foot ulcer
E11 Includes Notes
Per ICD-10-CM guidelines, E11 includes:
- Diabetes (mellitus) due to insulin secretory defect
- Diabetes NOS (not otherwise specified)
- Insulin resistant diabetes (mellitus)
E11 Excludes1 (Cannot code together)
The following codes are mutually exclusive with E11:
- Diabetes mellitus due to underlying condition (E08.-)
- Drug or chemical induced diabetes mellitus (E09.-)
- Gestational diabetes (O24.4-)
- Neonatal diabetes mellitus (P70.2)
- Postpancreatectomy diabetes mellitus (E13.-)
- Postprocedural diabetes mellitus (E13.-)
- Type 1 diabetes mellitus (E10.-)
Use Additional Code Instructions
When coding E11 diabetes, use additional code(s) to identify:
- Injectable non-insulin antidiabetic drugs (Z79.85)
- Insulin use (Z79.4)
- Oral antidiabetic drugs (Z79.84)
- Oral hypoglycemic drugs (Z79.84)
Type 1 Diabetes Mellitus (E10)
Type 1 diabetes is an autoimmune condition where the pancreas produces little or no insulin. The E10 category has 48 billable codes with a similar structure to E11.
Key Differences from Type 2
| Feature | Type 1 (E10) | Type 2 (E11) |
|---|---|---|
| Hyperosmolarity codes | Not available (E10.0 does not exist) | E11.00, E11.01 |
| Ketoacidosis | More common; E10.1x codes | Less common but exists; E11.1x |
| Presymptomatic code | E10.A - Presymptomatic | E11.A - In remission |
| Typical onset | Childhood/young adult | Adult onset |
| Insulin use | Always required | May or may not require |
Common E10 Billable Codes
- E10.9 - Type 1 diabetes mellitus without complications
- E10.10 - Type 1 diabetes mellitus with ketoacidosis without coma
- E10.65 - Type 1 diabetes mellitus with hyperglycemia
- E10.22 - Type 1 diabetes mellitus with diabetic chronic kidney disease
- E10.42 - Type 1 diabetes mellitus with diabetic polyneuropathy
Secondary Diabetes (E08, E09, E13)
E08: Diabetes Due to Underlying Condition
Use E08 codes when diabetes is secondary to another disease. The underlying condition must be coded first.
Common underlying conditions:
- Chronic pancreatitis
- Cystic fibrosis
- Hemochromatosis
- Cushing syndrome
- Acromegaly
Coding rule: Code first the underlying condition, then assign the appropriate E08 code.
E09: Drug or Chemical Induced Diabetes
E09 codes are used when diabetes is caused by medications or toxic substances.
Common causative agents:
- Glucocorticoids/steroids
- Antipsychotic medications
- Beta-blockers
- Thiazide diuretics
- Chemotherapy agents
Coding rules:
- Code first poisoning due to drug or toxin if applicable (T36-T65)
- Use additional code for adverse effect if applicable (T36-T50 with fifth or sixth character 5)
E13: Other Specified Diabetes Mellitus
E13 codes cover diabetes types not classified in E08-E11:
- Postpancreatectomy diabetes mellitus
- Postprocedural diabetes mellitus
- Secondary diabetes mellitus NEC (not elsewhere classified)
Diabetic Complications Coding
Ophthalmic Complications (x.3x)
Diabetic retinopathy is one of the most detailed subcategories with codes specifying:
- Retinopathy stage: Mild, moderate, severe nonproliferative; proliferative
- Macular edema: With or without
- Retinal detachment: Traction involving/not involving macula
Example codes for Type 2 diabetes:
- E11.311 - Type 2 diabetes with unspecified diabetic retinopathy with macular edema
- E11.3211 - Type 2 diabetes with mild nonproliferative diabetic retinopathy with macular edema, right eye
- E11.3512 - Type 2 diabetes with proliferative diabetic retinopathy with macular edema, left eye
Note: Use additional code to identify any associated macular edema (H35.81-).
Kidney Complications (x.2x)
Diabetic nephropathy codes:
- x.21 - Diabetic nephropathy (earliest stage)
- x.22 - Diabetic chronic kidney disease (use additional code for CKD stage N18.-)
- x.29 - Other diabetic kidney complication
Neurological Complications (x.4x)
- x.40 - Diabetic neuropathy, unspecified
- x.41 - Diabetic mononeuropathy
- x.42 - Diabetic polyneuropathy (most common)
- x.43 - Diabetic autonomic (poly)neuropathy
- x.44 - Diabetic amyotrophy
- x.49 - Other diabetic neurological complication
Circulatory Complications (x.5x)
- x.51 - Diabetic peripheral angiopathy without gangrene
- x.52 - Diabetic peripheral angiopathy with gangrene
- x.59 - Other circulatory complications
Skin Complications (x.62x)
- x.620 - Diabetic dermatitis
- x.621 - Diabetic foot ulcer (use additional code to identify site of ulcer L97.4-, L97.5-)
- x.622 - Other skin ulcer (use additional code to identify site of ulcer L97.1-L97.9, L98.41-L98.49)
- x.628 - Other skin complications
Common Coding Scenarios
Scenario 1: Type 2 Diabetes with Chronic Kidney Disease Stage 3
Clinical documentation: Patient with Type 2 diabetes mellitus and stage 3 chronic kidney disease due to diabetes.
Codes to assign:
1. E11.22 - Type 2 diabetes mellitus with diabetic chronic kidney disease
2. N18.3 - Chronic kidney disease, stage 3 (moderate)
Coding rationale: E11.22 captures the diabetic etiology of the CKD. Per guidelines, use additional code from N18.- to identify the stage.
Scenario 2: Type 2 Diabetes with Foot Ulcer and Peripheral Neuropathy
Clinical documentation: Patient with Type 2 diabetes, diabetic polyneuropathy, and a foot ulcer on the left heel.
Codes to assign:
1. E11.42 - Type 2 diabetes mellitus with diabetic polyneuropathy
2. E11.621 - Type 2 diabetes mellitus with foot ulcer
3. L97.422 - Non-pressure chronic ulcer of left heel, with fat layer exposed
Coding rationale: Multiple diabetic complications can be coded. The foot ulcer requires an additional code from L97.- to specify the site and severity.
Scenario 3: Steroid-Induced Diabetes with Hyperglycemia
Clinical documentation: Patient developed diabetes after long-term prednisone use for rheumatoid arthritis. Currently has elevated blood glucose levels.
Codes to assign:
1. E09.65 - Drug or chemical induced diabetes mellitus with hyperglycemia
2. T38.0X5A - Adverse effect of glucocorticoids, initial encounter
Coding rationale: Use E09 category for drug-induced diabetes. Add the adverse effect code to identify the causative drug.
Scenario 4: Type 1 Diabetes with DKA
Clinical documentation: Patient with Type 1 diabetes presents with diabetic ketoacidosis, no loss of consciousness.
Codes to assign:
1. E10.10 - Type 1 diabetes mellitus with ketoacidosis without coma
Coding rationale: DKA is a specific complication captured by the ketoacidosis codes. "Without coma" indicates the patient did not have altered consciousness.
Scenario 5: Diabetes Due to Chronic Pancreatitis with Retinopathy
Clinical documentation: Patient with diabetes secondary to chronic pancreatitis, now diagnosed with mild nonproliferative diabetic retinopathy without macular edema in both eyes.
Codes to assign:
1. K86.1 - Other chronic pancreatitis (code first)
2. E08.329 - Diabetes mellitus due to underlying condition with mild nonproliferative diabetic retinopathy without macular edema
3. H35.0291 - Mild nonproliferative diabetic retinopathy, bilateral (if laterality documented)
Coding rationale: E08 requires the underlying condition to be coded first. The retinopathy code requires identification of macular edema status.
Frequently Asked Questions
What is the difference between E11.9 and E11.65?
E11.9 (Type 2 diabetes mellitus without complications) is used when the patient has diabetes without any documented complications and without current hyperglycemia. E11.65 (Type 2 diabetes mellitus with hyperglycemia) is used when there is documented inadequately controlled diabetes or elevated blood glucose levels.
When should I code Z79.4 for insulin use?
Code Z79.4 (Long-term current use of insulin) as an additional code when the patient with Type 2 diabetes (E11) or secondary diabetes (E08, E09, E13) uses insulin. Do NOT assign Z79.4 with Type 1 diabetes (E10) because insulin use is inherent to Type 1.
Can I code E11 and E10 together?
No. Per the Excludes1 note, Type 1 and Type 2 diabetes codes are mutually exclusive. A patient cannot be coded as having both. If a patient has been diagnosed with both types, clarification from the provider is needed.
How do I code diabetes with multiple complications?
Assign as many codes from the diabetes category as necessary to describe all documented complications. Each complication should be captured with the most specific code available. For example, a patient with Type 2 diabetes, nephropathy, and neuropathy would receive both E11.22 and E11.42.
What is the correct code for "uncontrolled diabetes"?
"Uncontrolled" diabetes should be coded as diabetes with hyperglycemia (x.65 code) unless the documentation specifies hypoglycemia. Query the provider if the type of "uncontrolled" is unclear.
Is E11.9 billable?
Yes, E11.9 (Type 2 diabetes mellitus without complications) is a billable code and is appropriate when the patient has Type 2 diabetes without any documented complications.
How do I code diabetes in pregnancy?
Gestational diabetes is coded from category O24.4, not E10-E13. Pre-existing diabetes in pregnancy is coded using the O24 category with additional codes from E10-E13 to identify the type.
Quick Reference Table
| Type of Diabetes | Category | Without Complications | With Hyperglycemia | With CKD | With Neuropathy |
|---|---|---|---|---|---|
| Due to underlying condition | E08 | E08.9 | E08.65 | E08.22 | E08.42 |
| Drug-induced | E09 | E09.9 | E09.65 | E09.22 | E09.42 |
| Type 1 | E10 | E10.9 | E10.65 | E10.22 | E10.42 |
| Type 2 | E11 | E11.9 | E11.65 | E11.22 | E11.42 |
| Other specified | E13 | E13.9 | E13.65 | E13.22 | E13.42 |
Related Resources
- Browse all E08-E13 diabetes codes
- Search diabetes codes
- AI Clinical Note Analyzer - Extract diabetes codes from clinical documentation
- Endocrine Chapter Overview
References and Official Sources
- CMS ICD-10-CM Official Guidelines for Coding and Reporting
- American Diabetes Association Clinical Practice Guidelines
- CMS Medicare Learning Network: ICD-10 Coding Resources
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Last updated: January 2025. Code data reflects ICD-10-CM 2026 version.
Disclaimer: This guide is for educational purposes only. Always verify codes against current official ICD-10-CM guidelines and consult with certified coding professionals for specific coding questions.