ICD-10 in Action: Coding guidelines and conventions – Excludes1 and Excludes2 notes

June 22, 2018

This AmeriHealth series, ICD-10 in Action, features articles to recap some of the ICD-10 diagnosis code changes, introduce new coding scenarios, and/or communicate updates to ICD-10 coding conventions.

The ICD-10-CM Manual contains official guidelines for coding and reporting. There are coding conventions, general coding guidelines, and chapter-specific guidelines. These conventions and guidelines are rules and instructions that must be followed to classify and assign the most appropriate code. Understanding these guidelines and conventions are key to selecting the most appropriate code assignment.

  • Conventions. A set of rules for use of the classification independent of the guidelines. Coding conventions and instructions of the classification take precedence over guidelines. (e.g., Code First).
  • General guidelines. A set of rules and sequencing instructions for using the Tabular List and Alphabetic Index. These guidelines provide rules such as how to locate a code and obtain level of detail.
  • Chapter-specific guidelines. A set of rules for specific diagnoses and conditions in a particular classification.

As with ICD-9, adherence to these guidelines is required under the Health Insurance Portability and Accountability Act (HIPAA).

Coding Convention: Excludes Notes

According to the ICD-10-CM Official Guidelines for Coding and Reporting, there are two types of excludes notes, Excludes1 and Excludes2. Each type has a different definition for use, but they are both similar in that they indicate that codes excluded from each other are independent of each other.


Excludes1 is a pure excludes note. It means NOT CODED HERE. An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 note is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

An exception to the Excludes1 definition is the circumstance when the two conditions are unrelated to each other. If it is not clear whether the two conditions involving an Excludes1 note are related or not, request clarity from the provider. For example, code F45.8, Other somatoform disorders, has an Excludes1 note for sleep related teeth grinding (G47.63), because teeth grinding is an inclusion term under F45.8. Only one of these two codes should be assigned for teeth grinding. However, psychogenic dysmenorrhea is also an inclusion term under F45.8. A patient could have both this condition and sleep related teeth grinding. In this case, the two conditions are clearly unrelated to each other. It would be appropriate to report F45.8 and G47.63 together.


Excludes2 represents NOT INCLUDED HERE. An Excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.

Coding examples

Excludes1 and Excludes2 Notes

  • A15.4: Tuberculosis of intrathoracic lymph nodes
    Excludes1: A15.7: Primary respiratory tuberculosis
    Excludes1: P37.0: Congenital tuberculosis
  • A18.6: Tuberculosis of (inner) (middle) ear
    Excludes2: A18.4: Tuberculosis of skin and subcutaneous tissue
    Note: A18.4 represent tuberculosis of external ear
  • C79.2: Secondary malignant neoplasm of skin
    Excludes1: C7B.1: Secondary Merkel cell carcinoma
    Note: C7B.1 is a type of skin cancer. The more specific code should be used.
  • C79.51: Secondary malignant neoplasm of bone
    Excludes1: C7B.03: Secondary carcinoid tumors of bone
  • D24.1: Benign neoplasm of right breast
    Excludes2: D22.5: Melanocytic nevi of trunk
    Excludes2: D23.5: Other benign neoplasm of skin of trunk
    Note: D22.5 and D23.5 represent benign neoplasm of the skin of the breast.
  • D29.1: Benign neoplasm of prostate
    Excludes1: N40.0:​​ Benign prostatic hyperplasia without lower urinary tract sympto​ms
    Excludes1: N40.1: Benign prostatic hyperplasia with lower urinary tract symptoms
    Excludes1: N40.2: Nodular prostate without lower urinary tract symptoms
    Excludes1: N40.3: Nodular prostate with lower urinary tract symptoms
    Note: The range of N40._ _ : Represent enlarged prostate
  • E36.01: Intraoperative hemorrhage and hematoma of an endocrine system organ or structure complicating an endocrine system procedure
    Excludes1: E36.11: Accidental puncture and laceration of an endocrine system organ or structure during an endocrine system procedure
    Excludes1: E36.12: Accidental puncture and laceration of an endocrine system organ or structure during other procedure
  • F05: Delirium due to known physiological condition
    Excludes1: R41.0: Disorientation, unspecified
    Excludes2: F10.231: Alcohol dependence with withdrawal delirium
    Excludes2: F10.921: Alcohol use, unspecified with intoxication delirium
    Note: R41.0 represent delirium NOS, F10.231 and F10.921 represent alcohol induced delirium tremens.
  • G44.41: Drug-induced headache, not elsewhere classified, intractable
    Excludes1: R51: Headache
    Excludes2: G97.1: Other reaction to spinal and lumbar puncture
    Note: G97.1 may represent headache due to lumbar puncture.
  • H05.30: Unspecified deformity of orbit
    Excludes1: Q10.7: Congenital malformation of orbit
    Note: This is a case of the acquired versus the congenital form of the same condition. This can never be reported together.

Stay tuned

We will continue to communicate ICD-10-specific information through this article series to review some of the ICD-10 diagnosis code changes. We encourage you to keep up with the latest news and information by visiting the ICD-10 section of our website for AmeriHealth New Jersey or AmeriHealth Pennsylvania.