ICD-10 Code G51.4 – Facial myokymia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code G51.4 – Facial myokymia
What it is
Facial myokymia means involuntary, fine, rippling movements of the facial muscles. You use this code when documentation identifies facial muscle twitching as the diagnosis.
Clinical signs
Typical findings include continuous or intermittent undulating contractions, often described as worm-like movement under the skin. Clinical features vary; refer to documentation.
When to use this code
Use G51.4 when the provider documents facial myokymia as the confirmed reason for the visit or as a significant diagnosis. It may appear as a neurologic finding during evaluation of facial twitching or abnormal facial movement. Code the documented condition, not a symptom alone, unless that is all the record supports.
Do not use for
Do not use this code for generalized muscle twitching, eyelid spasm, or other facial movement disorders unless facial myokymia is specifically documented. Check documentation.
Coding tip
If the note only says “facial twitching,” query whether the provider means facial myokymia before assigning G51.4.