ICD-10 Code G44.099 – Other trigeminal autonomic cephalgias (TAC), not intractable (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G44.099 – Other trigeminal autonomic cephalgias (TAC), not intractable
What it is
This code identifies other trigeminal autonomic cephalgias that are not described elsewhere and are not documented as intractable. These are primary headache disorders with short, severe attacks and autonomic features on one side of the head.
Clinical signs
Typical findings include unilateral head pain with tearing, nasal congestion, eyelid swelling, facial flushing, or restlessness during attacks. Clinical features vary; refer to documentation.
When to use this code
Use G44.099 when the record specifies an “other” TAC and does not identify a more specific trigeminal autonomic cephalalgia. You should also use it when the provider documents the condition as not intractable. Check documentation if the note only says headache without TAC features.
Do not use for
Do not use this code for migraine, cluster headache, or other specifically named headache disorders when a more exact code applies. Do not use it if the provider documents intractable disease or gives a different headache diagnosis.
Coding tip
Code from the provider’s exact diagnosis wording, and confirm whether the headache is documented as intractable or not intractable.