ADHD ICD-10 Codes: The Complete Guide to Diagnostic Classification

If you’re looking for the ICD-10 code for ADHD, the general code is F90.9 (Attention-deficit hyperactivity disorder, unspecified type). However, depending on the specific presentation of ADHD symptoms, more precise codes may be applicable.

In today’s healthcare environment, ICD-10 codes serve as the universal language for diagnosis, medical billing, and research. These standardized codes help healthcare providers communicate precise diagnostic information, facilitate accurate insurance claims, and contribute to meaningful epidemiological research on conditions like ADHD.

This comprehensive guide will walk you through everything you need to know about ADHD ICD-10 codes, including the different types of ADHD classifications, recent updates, practical applications in clinical settings, and how to avoid common coding errors. Whether you’re a healthcare provider, billing specialist, or simply trying to understand your medical documentation better, this information will prove invaluable.

Understanding ICD-10: The Framework for ADHD Diagnosis

The International Classification of Diseases, 10th Revision (ICD-10) is a globally recognized diagnostic classification system developed by the World Health Organization (WHO). Implemented in the United States in 2015, replacing the outdated ICD-9 system, it provides a comprehensive framework for classifying diseases, disorders, injuries, and health conditions.

Who Uses ICD-10 Codes?

ICD-10 codes are utilized by a wide range of healthcare professionals and organizations:

• Physicians and psychiatrists use them to document diagnoses
• Psychologists and therapists reference them in clinical assessments
• Hospitals and clinics require them for patient records
• Insurance companies rely on them for claims processing
• Researchers and epidemiologists use them to track disorder prevalence and outcomes

Why Accurate ADHD Coding Matters

Precision in ICD-10 coding for ADHD is crucial for several reasons:

• Billing accuracy: Ensures proper reimbursement from insurance providers
• Treatment planning: Helps guide appropriate interventions
• Care coordination: Facilitates communication between healthcare providers
• Research validity: Contributes to accurate statistical data on ADHD prevalence
• Patient advocacy: Supports patient access to necessary services and accommodations

The Anatomy of an ICD-10 Code

ICD-10 codes follow a structured format:

• They begin with a letter (F for mental health disorders)
• Followed by numbers that specify the category and subcategory
• May include decimal points for greater specificity
• For ADHD, codes begin with F90, followed by a decimal and additional digits to specify the presentation type

The Specific ADHD ICD-10 Codes (F90 – F90.9)

Let’s examine each ADHD ICD-10 code in detail:

F90.0: A Deep Dive into the Predominantly Inattentive Type ICD-10 Code

The F90.0 code classifies ADHD presentations where inattention symptoms predominate. This presentation was formerly known as ADD (Attention Deficit Disorder) in earlier diagnostic frameworks.

Diagnostic Criteria (DSM-5):

• Six or more inattention symptoms (five for adults)
• Symptoms present for at least 6 months
• Symptoms inconsistent with developmental level
• Symptoms negatively impact functioning
• Fewer than six hyperactivity-impulsivity symptoms

Clinical Presentation Examples:

• Difficulty sustaining attention in tasks
• Frequently makes careless mistakes
• Often fails to follow through on instructions
• Easily distracted by extraneous stimuli
• Often forgetful in daily activities
• Difficulty organizing tasks and activities

Coding Notes:

• Should be used when inattentive symptoms clearly predominate
• Documentation should specifically note the predominance of inattentive symptoms

F90.1: Understanding the Hyperactive-Impulsive Type ICD-10 Code

The F90.1 code is used when hyperactivity and impulsivity are the primary symptoms, with fewer inattentive symptoms present.

Diagnostic Criteria:

• Six or more hyperactivity-impulsivity symptoms (five for adults)
• Symptoms present for at least 6 months
• Symptoms inconsistent with developmental level
• Symptoms negatively impact functioning
• Fewer than six inattention symptoms

Clinical Presentation Examples:

• Fidgeting or tapping hands/feet
• Difficulty remaining seated when expected
• Running or climbing excessively (restlessness in adults)
• Difficulty engaging in quiet activities
• Often “on the go” or acting as if “driven by a motor”
• Talking excessively, blurting out answers
• Difficulty waiting turn, frequently interrupting others

Coding Notes:

• Less commonly diagnosed than inattentive or combined types
• More frequently diagnosed in young children
• Documentation should specifically note the predominance of hyperactive-impulsive symptoms

F90.2: Combined Type

The F90.2 code represents ADHD with a mix of both inattentive and hyperactive-impulsive symptoms.

Diagnostic Criteria:

• Six or more symptoms from both the inattention and hyperactivity-impulsivity categories (five for adults)
• Symptoms present for at least 6 months
• Symptoms negatively impact functioning

Clinical Presentation Examples:

• Displays significant symptoms from both categories
• Often the most functionally impairing presentation
• Symptoms may fluctuate between domains over time

Coding Notes:

• Most commonly diagnosed ADHD presentation
• Requires documentation of significant symptoms in both domains

F90.8: Other Specified Attention-Deficit Hyperactivity Disorder

This code is used for ADHD presentations that cause clinically significant distress but don’t meet the full criteria for other F90 codes.

When to Use This Code:

• When partial symptom criteria are met (e.g., 4-5 symptoms)
• When onset is after age 12 but all other criteria are met
• When atypical presentation occurs but is clearly ADHD-related

Specific Examples:

• “ADHD, in partial remission” – when previously diagnosed but now with fewer symptoms
• “ADHD with late onset” – when symptoms began after age 12
• “ADHD with atypical presentation” – when symptoms don’t clearly fit other categories

F90.9: Attention-Deficit Hyperactivity Disorder, Unspecified Type

This is the general code used when ADHD is diagnosed but the specific presentation type hasn’t been determined.

When to Use This Code:

• Initial assessment when type hasn’t been determined
• When insufficient information is available to make a specific diagnosis
• When presentation is mixed or fluctuating and doesn’t clearly fit another category

Limitations:

• Less specific for treatment planning
• Less informative for research purposes
• May lead to insurance reimbursement complications
• Should be updated to a more specific code when additional information becomes available

Comparison Table: ADHD ICD-10 Codes

ICD-10 Code	Description	Key Diagnostic Criteria	Typical Symptoms
F90.0	Predominantly Inattentive Type	≥6 inattention symptoms <br>< 6 hyperactivity-impulsivity symptoms	Poor attention to detail, difficulty sustaining attention, poor organization, forgetfulness
F90.1	Predominantly Hyperactive-Impulsive Type	≥6 hyperactivity-impulsivity symptoms <br><6 inattention symptoms	Fidgeting, leaving seat, excessive running/climbing, difficulty with quiet activities, talking excessively
F90.2	Combined Type	≥6 symptoms from both categories	Significant symptoms from both inattention and hyperactivity-impulsivity domains
F90.8	Other Specified ADHD	Doesn’t meet full criteria but has significant symptoms	Partial symptom criteria, late onset, atypical presentation
F90.9	ADHD, Unspecified Type	ADHD diagnosis without specified type	Used when type hasn’t been determined or information is insufficient

Diagnostic Criteria and Considerations

DSM-5 Criteria for ADHD

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) provides the clinical criteria used to diagnose ADHD, which informs ICD-10 coding:

Inattention (6+ symptoms, 5+ for adults):

1. Often fails to give close attention to details or makes careless mistakes
2. Often has difficulty sustaining attention in tasks
3. Often does not seem to listen when spoken to directly
4. Often does not follow through on instructions
5. Often has difficulty organizing tasks and activities
6. Often avoids tasks requiring sustained mental effort
7. Often loses things necessary for tasks or activities
8. Is often easily distracted by extraneous stimuli
9. Is often forgetful in daily activities

Hyperactivity-Impulsivity (6+ symptoms, 5+ for adults):

1. Often fidgets with hands/feet or squirms in seat
2. Often leaves seat when remaining seated is expected
3. Often runs or climbs excessively (restlessness in adults)
4. Often unable to play or engage in leisure activities quietly
5. Is often “on the go” or acting as if “driven by a motor”
6. Often talks excessively
7. Often blurts out answers before questions are completed
8. Often has difficulty waiting turn
9. Often interrupts or intrudes on others

Additional DSM-5 Requirements:

• Several symptoms present before age 12
• Symptoms present in two or more settings
• Symptoms interfere with functioning
• Symptoms not better explained by another disorder

Differential Diagnosis

Several conditions may mimic ADHD symptoms, requiring careful differential diagnosis:

• Anxiety disorders: May cause inattention due to worry; differentiate by assessing if attention improves when anxiety is addressed
• Depression: Can cause concentration difficulties; differentiate by noting if inattention occurs only during depressive episodes
• Learning disabilities: May cause avoidance of tasks requiring sustained mental effort; differentiate by comprehensive psychoeducational assessment
• Oppositional defiant disorder: May appear as impulsivity; differentiate by noting if behavior is primarily defiance-based
• Autism spectrum disorder: May cause difficulty following social rules; differentiate by assessing for restricted interests and social communication deficits
• Sleep disorders: May cause inattention due to fatigue; differentiate by addressing sleep issues and reassessing symptoms

Comorbidity Coding Considerations

ADHD frequently co-occurs with other conditions, requiring additional coding:

• Anxiety disorders (F41.x): Document both the ADHD code and appropriate anxiety code
• Depression (F32.x, F33.x): List both ADHD and depression codes
• Oppositional defiant disorder (F91.3): Commonly co-occurs with ADHD, especially hyperactive type
• Specific learning disorder (F81.x): Requires separate coding
• Autism spectrum disorder (F84.0): Can be coded alongside ADHD in DSM-5/ICD-10

Example: A patient with ADHD-Combined type and Generalized Anxiety Disorder would be coded as:

• F90.2 (ADHD, Combined type)
• F41.1 (Generalized anxiety disorder)

Practical Applications and Coding Best Practices

Step-by-Step Guide to ADHD Coding

1. Gather comprehensive assessment data:
   • Clinical interview with patient
   • Standardized rating scales
   • Observational data
   • Collateral information from teachers/parents/spouses
2. Determine symptom presentation:
   • Count number of inattentive symptoms
   • Count number of hyperactive-impulsive symptoms
3. Select the appropriate code:
   • F90.0 for predominantly inattentive
   • F90.1 for predominantly hyperactive-impulsive
   • F90.2 for combined presentation
   • F90.8 for other specified ADHD
   • F90.9 only if type cannot be determined
4. Document comorbid conditions and assign additional codes as needed
5. Update coding as presentation changes over time

Documentation Requirements

For proper ADHD ICD-10 coding, documentation should include:

• Symptom inventory: Specific symptoms meeting DSM-5 criteria
• Onset and duration: When symptoms began and how long they’ve persisted
• Functional impact: How symptoms affect academic, occupational, or social functioning
• Multiple settings: Evidence of symptoms across two or more settings
• Differential considerations: Rule-out of alternative explanations
• Assessment methodology: Rating scales, interviews, observations used
• Rationale for specific code selection: Why this particular code was chosen

Coding Scenarios

Scenario 1: 9-year-old boy with difficulty sustaining attention, frequent careless mistakes, organizational problems, but minimal hyperactivity.

• Correct Code: F90.0 (Predominantly Inattentive Type)
• Rationale: Meets criteria for inattentive symptoms without significant hyperactivity

Scenario 2: 6-year-old girl who constantly fidgets, talks excessively, interrupts others, and has some mild attentional issues.

• Correct Code: F90.1 (Predominantly Hyperactive-Impulsive Type)
• Rationale: Hyperactive-impulsive symptoms predominate

Scenario 3: 35-year-old adult with lifelong history of both inattention and hyperactivity affecting work performance.

• Correct Code: F90.2 (Combined Type)
• Rationale: Meets adult criteria for both symptom domains

Billing and Insurance Considerations

Common Billing Challenges:

• Insurance requiring specific documentation of symptoms
• Requirement for standardized assessments
• Limitations on coverage for certain ADHD presentations
• Prior authorization requirements

Tips for Avoiding Claim Denials:

• Use the most specific code available
• Ensure documentation supports the selected code
• Include standardized assessment results
• Document functional impairment clearly
• Update coding as presentation changes

Importance of Accurate Documentation:

• Detailed clinical notes supporting diagnostic criteria
• Evidence of comprehensive assessment
• Documentation of symptom impact on functioning
• Clear rationale for treatment recommendations

ICD-10 Updates and Changes

The ICD-10 coding system undergoes periodic updates to reflect evolving understanding of disorders. For the most current information:

• Visit the World Health Organization (WHO) ICD website
• Check the Centers for Disease Control and Prevention (CDC) ICD-10-CM webpage
• Consult your professional organization’s coding resources

Recent developments to be aware of:

• Alignment of ICD-10 with DSM-5 criteria
• Enhanced specificity in ADHD subtypes
• Improved guidance on comorbidity coding

Common Coding Errors and How to Avoid Them

1. Misunderstanding Diagnostic Criteria

Error: Coding based on informal description rather than specific diagnostic criteria Solution: Use standardized assessment tools and reference DSM-5 criteria directly

2. Insufficient Documentation

Error: Documenting “patient has ADHD” without supporting evidence Solution: Document specific symptoms, onset, duration, and functional impact

3. Using Unspecified Codes Unnecessarily

Error: Defaulting to F90.9 when more specific coding is possible Solution: Conduct thorough assessment to determine specific presentation type

4. Incorrect Comorbidity Coding

Error: Failing to code for significant comorbid conditions Solution: Document and code all clinically significant conditions

Resources and Further Reading

Official ICD-10 Resources

• World Health Organization (WHO) ICD-10 Online Browser
• CDC’s National Center for Health Statistics ICD-10-CM

Professional Organizations

• American Psychiatric Association (APA)
• CHADD (Children and Adults with ADHD)
• ADDA (Attention Deficit Disorder Association)

Recommended Reading

• DSM-5 Handbook of Differential Diagnosis by Michael B. First
• Diagnosing and Treating ADHD: A Professional’s Guide by Carol Watkins
• Taking Charge of Adult ADHD by Russell A. Barkley

Frequently Asked Questions

Q: What is the ICD-10 code for ADHD? A: The general code is F90.9 (Attention-deficit hyperactivity disorder, unspecified type), but more specific codes include F90.0 (predominantly inattentive type), F90.1 (predominantly hyperactive-impulsive type), and F90.2 (combined type).

Q: What are the different types of ADHD codes? A: The main ADHD ICD-10 codes are F90.0 (predominantly inattentive), F90.1 (predominantly hyperactive-impulsive), F90.2 (combined type), F90.8 (other specified ADHD), and F90.9 (unspecified ADHD).

Q: Who uses ICD-10 codes? A: Healthcare providers, insurance companies, hospitals, researchers, and public health officials all use ICD-10 codes for diagnosis, billing, and data collection purposes.

Q: How is the ICD-10 code used for ADHD? A: ICD-10 codes for ADHD are used to document the specific type of ADHD, facilitate insurance billing, guide treatment planning, and contribute to research data.

Q: What is the difference between F90.0, F90.1, and F90.2? A: F90.0 is for predominantly inattentive ADHD, F90.1 is for predominantly hyperactive-impulsive ADHD, and F90.2 is for combined type ADHD with significant symptoms in both domains.

Q: Can I use F90.9 if I don’t know the specific type of ADHD? A: F90.9 should only be used temporarily when insufficient information is available to determine the specific type. Best practice is to conduct a thorough assessment and update to a more specific code when possible.

Q: Where can I find the official ICD-10 coding guidelines? A: Official ICD-10 guidelines can be found on the WHO website, the CDC’s National Center for Health Statistics website, or through professional coding organizations.

Q: How often are ICD-10 codes updated? A: The ICD-10-CM (Clinical Modification) used in the United States is updated annually, with changes taking effect on October 1 of each year.

Q: What are the DSM-5 criteria for ADHD? A: DSM-5 criteria include at least six symptoms (five for adults) of inattention and/or hyperactivity-impulsivity, onset before age 12, symptoms in multiple settings, functional impairment, and symptoms not better explained by another condition.

Conclusion

Accurate ADHD coding using the ICD-10 system is essential for proper diagnosis, effective treatment planning, appropriate insurance reimbursement, and valid research data. By understanding the specific codes for different ADHD presentations (F90.0 for predominantly inattentive, F90.1 for predominantly hyperactive-impulsive, and F90.2 for combined type) and following best practices for documentation, healthcare providers can ensure that patients receive the care they need.

Remember that coding should be specific whenever possible, with F90.9 (unspecified type) used only when insufficient information is available for a more detailed diagnosis. Attention to comorbid conditions and differential diagnosis further enhances the accuracy and usefulness of ADHD coding.

For complex coding questions or situations, consult with coding specialists or refer to official resources from the WHO, CDC, or professional organizations specializing in ADHD. By maintaining high standards of diagnostic precision and coding accuracy, we can improve both individual patient care and our collective understanding of ADHD.