What are the relevant F codes from the ICD-10 classification system for diagnosing and billing a patient with bipolar disorder?

ICD-10 F Codes for Bipolar Disorder

The relevant ICD-10 F codes for bipolar disorder fall under the F30-F31 category, with F31 being the primary code for bipolar affective disorder, differentiated by current episode type and severity. 1

Primary Diagnostic Codes

F31 - Bipolar Affective Disorder

• F31.0 - Bipolar affective disorder, current episode hypomanic 1
• F31.1 - Bipolar affective disorder, current episode manic without psychotic symptoms 1
• F31.2 - Bipolar affective disorder, current episode manic with psychotic symptoms 1
• F31.3 - Bipolar affective disorder, current episode mild or moderate depression 1
• F31.4 - Bipolar affective disorder, current episode severe depression without psychotic symptoms 1
• F31.5 - Bipolar affective disorder, current episode severe depression with psychotic symptoms 1
• F31.6 - Bipolar affective disorder, current episode mixed 1
• F31.7 - Bipolar affective disorder, currently in remission 1
• F31.8 - Other bipolar affective disorders 1
• F31.9 - Bipolar affective disorder, unspecified 1

F30 - Manic Episode (Single Episode)

• F30.0 - Hypomania 1
• F30.1 - Mania without psychotic symptoms 1
• F30.2 - Mania with psychotic symptoms 1
• F30.8 - Other manic episodes 1
• F30.9 - Manic episode, unspecified 1

Key Diagnostic Distinctions in ICD-10

Duration Requirements

• Manic episodes must last at least 1 week or require hospitalization in ICD-10, consistent with DSM-IV-TR criteria 1
• Hypomanic episodes require at least 4 days duration 1
• Mixed episodes require symptoms meeting criteria for both manic and depressive episodes lasting at least 7 days 1

Bipolar I vs Bipolar II Differentiation

• Bipolar I disorder requires occurrence of at least one manic or mixed episode, with or without depressive episodes 1, 2
• Bipolar II disorder requires periods of major depression and hypomania but no full manic or mixed episodes 1, 2
• ICD-10 does not formally distinguish between Bipolar I and Bipolar II as separate diagnostic categories like DSM-5 does, instead using the F31 code with episode specifiers 1, 3

Important Clinical Considerations

Rapid Cycling Specification

• Rapid cycling is defined as at least four mood episodes in one year, with episodes still meeting prerequisite duration criteria (7 days for mania, 4 days for hypomania) 1
• This differs from some pediatric literature definitions where "cycling" refers to mood changes within an episode 1

Bipolar Disorder Not Otherwise Specified

• F31.8 is used for cases not meeting full criteria for other bipolar diagnoses, including presentations common in youth that don't match classic adult patterns 1
• This code encompasses ultrarapid cycling (5-364 cycles per year) and ultradian cycling (>365 cycles per year), though these terms are not formally adopted in ICD-10 1

Common Coding Pitfalls

Episode Specification is Mandatory

• Always specify the current episode type when using F31 codes - using F31.9 (unspecified) should be avoided when sufficient clinical information exists to determine episode type 1
• The current episode determines the fourth digit, making accurate assessment of present symptoms critical for proper coding 1

Mixed Episodes vs Rapid Cycling

• F31.6 (mixed episode) requires simultaneous manic and depressive symptoms for at least 7 days 1
• Rapid cycling is not a separate code but rather a course specifier that should be documented clinically 1
• Mixed states occur in approximately 40% of bipolar patients over a lifetime and require the mixed episode code when present 4

First Episode vs Recurrent

• F30 codes are used for single manic episodes without history of previous mood episodes 1
• Once a patient has had multiple episodes, F31 codes should be used even if currently in remission 1

ICD-11 Updates (For Future Reference)

• ICD-11 has introduced dimensional symptom specifiers for depressive episodes in bipolar disorder, including melancholic features, anxiety symptoms, panic attacks, and seasonal pattern qualifiers 1
• Severity ratings (mild, moderate, severe) and remission status (partial or full) can now be specified more granularly 1
• These changes improve clinical utility and allow more detailed characterization of symptom profiles 1