G44.021 Chronic cluster headache, intractable

The following code(s) above G44.021 may contain annotation back-references that may be applicable to G44.021:

• Diseases of the nervous system (G00-G99)
• Chronic cluster headache (G44.02)

Diagnosis Index

Headache R51.9
- Cluster G44.009
-- Chronic G44.029
--- Intractable G44.021