ICD-10 Code for Underdosing

The default ICD-10-CM 2027 code for underdosing is Z91.14 – Patient's other noncompliance with medication regimen (a header – choose a more specific code). More specific codes depend on the details documented, as listed in the official index (5 codes, 4 billable).

Main code
Z91.14 – Patient's other noncompliance with medication regimen
Billable
No – header code
See also
Table of Drugs and Chemicals, categories T36-T50, with final character 6

Index entries for Underdosing

How to choose the right code

Start with the main term, then pick the indented subterm that matches the documentation (type, cause, site, laterality, episode of care). Always confirm the code in the tabular list: follow its Excludes1/Excludes2, “code first” and “use additional code” notes, and add a 7th character where required.

Source: CDC/NCHS ICD-10-CM FY2027 alphabetic index.