Z91.A3

Billable code

Caregiver's unintentional underdosing of patient's medication regimen

The ICD-10 code for caregiver's unintentional underdosing of patient's medication regimen is Z91.A3.

Clinical notes

Code first

This code represents a manifestation of an underlying disease. Coding convention requires the underlying (etiology) code to be sequenced first, with this code listed second.

underdosing of medication (T36-T50) with fifth or sixth character 6

Documentation support

General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.

•This code represents a manifestation. Documentation should identify the underlying condition, which must be coded first.
•As a general rule, code to the highest level of specificity supported by the documentation in the medical record.

Related codes in this category

Z91.A1Caregiver's noncompliance with patient's dietary regimennon-billable header
Z91.A2Caregiver's intentional underdosing of patient's medication regimennon-billable header
Z91.A4Caregiver's other noncompliance with patient's medication regimennon-billable header
Z91.A5Caregiver's noncompliance with patient's renal dialysisnon-billable header
Z91.A9Caregiver's noncompliance with patient's other medical treatment and regimennon-billable header
Z91.A3Caregiver's unintentional underdosing of patient's medication regimen

Associated MS-DRGs

Z91.A3 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.

Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.