ICD-10 Code R51.9: Headache, unspecified
Symptoms, signs and abnormal findings
ICD-10 code R51.9 identifies unspecified headache, used when no more specific headache diagnosis is established.
Coding guidance
R51 was expanded into R51.0 (headache with orthostatic component) and R51.9 (headache, unspecified).
R51 alone is no longer valid and will be rejected on claims.
Migraine, tension-type and cluster headaches have specific codes under G43 and G44.
Documentation and specificity notes
- Use a specific headache diagnosis such as G43.- for migraine whenever documentation supports it.
- Verify your code set is current: the deprecated R51 causes rejections.
- Document duration, character and associated symptoms.
Related codes
This page provides a general summary for educational purposes and is not a substitute for the official ICD-10-CM code set, the ICD-10-CM Official Guidelines for Coding and Reporting, or payer policy. Code sets are updated annually, verify against the current official release before billing.
FAQ
ICD-10 R51.9, frequently asked questions questions
- What is ICD-10 code R51.9?
- ICD-10 code R51.9 identifies unspecified headache, used when no more specific headache diagnosis is established.
- Is R51.9 a billable ICD-10 code?
- Yes. R51.9 is a billable and specific ICD-10-CM code that may be used to indicate a diagnosis for reimbursement purposes, provided documentation supports it.
- What documentation supports R51.9?
- Use a specific headache diagnosis such as G43.- for migraine whenever documentation supports it. Verify your code set is current: the deprecated R51 causes rejections. Document duration, character and associated symptoms.
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