ICD-10-CM > G00-G99 > G40-G47 > G44 > G44.3 > G44.30 G44.30 Post-traumatic headache, unspecified Non-Billable/Non-Specific Codes G44.301Post-traumatic headache, unspecified, intractableG44.309Post-traumatic headache, unspecified, not intractable