I20.9 - Angina pectoris, unspecified

Clinical Definition

A chronic migraine is a primary headache disorder characterized by 15 or more headache days per month, of which at least 8 are migrainous, for more than 3 months. Without aura means there are no associated neurological symptoms preceding the headache.

Documentation Requirements

• Must explicitly document:

  • "Chronic migraine" terminology

  • Duration (> 3 months)

  • Frequency (≥15 headache days/month)

  • Specify "without aura"

  • Document failed preventive treatments if applicable

  • Pain characteristics (pulsating, unilateral, etc.)

  • Associated symptoms (nausea, photophobia, etc.)

Common Synonyms

• Transformed migraine

• Chronic daily headache

• Refractory migraine

• Status migrainosus (if prolonged attack)

Coding Conflicts

Excludes1:

• G43.101 (Migraine with aura, intractable)

• G44.1 (Vascular headache, not elsewhere classified)

Excludes2:

• R51 (Headache)

• G44.2 (Tension-type headache)

Scribing.io Automation

The AI scribe automatically identifies:

• Temporal patterns ("15+ days per month")

• Duration keywords ("ongoing", "chronic", "persistent")

• Absence of aura symptoms

• Treatment resistance language

• Associated symptoms

When documenting, the AI highlights these elements in real-time to ensure complete capture of chronicity criteria and absence of aura symptoms.