ICD-10 Code G44.091 – Other trigeminal autonomic cephalgias (TAC), intractable (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G44.091 – Other trigeminal autonomic cephalgias (TAC), intractable
What it is
This code identifies a trigeminal autonomic cephalalgia that is documented as intractable, meaning the headache disorder is difficult to control or persists despite usual management. It is used when the provider specifies this TAC category rather than a more specific headache diagnosis.
Clinical signs
Clinical features vary; refer to documentation. TACs typically involve severe unilateral head pain with ipsilateral autonomic symptoms such as tearing, nasal congestion, or eye redness, but the exact pattern depends on the specific disorder.
When to use this code
Use G44.091 when the record clearly states other trigeminal autonomic cephalalgia and also notes that it is intractable. Apply it for encounters focused on ongoing evaluation, follow-up, or management of a persistent TAC when no more specific code is documented.
If the note only says headache, migraine, or cluster headache, do not assume this code. Check documentation for the exact headache type and whether intractability is explicitly recorded.
Do not use for
Do not use this code for unspecified headache disorders, migraine, or cluster headache unless the documentation specifically supports a TAC diagnosis. Avoid it when intractability is not stated.
Coding tip
Code only from the provider’s exact wording; if the TAC subtype or intractable status is missing, check documentation.