Z91.128
✓ BillablePatient's intentional underdosing of medication regimen for other reason
Factors influencing health status and contact with health services (Z00-Z99)
📋 Code Instructions
from Z91.12- • Code first: underdosing of medication (T36-T50) with fifth or sixth character 6
✅ No additional coding notes for Z91.128
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CodeZ91.128
BillableYes
ParentZ91.12
CategoryFactors influencing health status and contact with health services (Z00-Z99)
Excludes10 rule(s)
Excludes20 note(s)
Data Source
CMS ICD-10-CM 2026 Tabular List
Updated October 1, 2025 (FY2026)