Z91.A3 — Caregiver's unintentional underdosing of patient's medication regimen
Z91.A3 is a billable, specific ICD-10-CM code for caregiver's unintentional underdosing of patient's medication regimen. It is valid for submission on a claim.
Risk adjustment
Z91.A3 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
Z91.A3 is named in 4 Medicare coverage policies — 4 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A54799Billing and Coding: Urine Drug Testing
- A55001Billing and Coding: Urine Drug Testing
- A56818Billing and Coding: Urine Drug Testing
- A59416Billing and Coding: Urine Drug Testing
How Z91.A3 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to Z91.A3.
- Noncompliance›with›medication regimen NEC›underdosing›unintentional NEC›by caregiver
Related codes at this level
Codes that share Z91.A. If Z91.A3 is not quite right, the correct code is usually one of these.
- Z91.A1Caregiver's noncompliance with patient's dietary regimen
- Z91.A2Caregiver's intentional underdosing of patient's medication regimen
- Z91.A4Caregiver's other noncompliance with patient's medication regimen
- Z91.A5Caregiver's noncompliance with patient's renal dialysis
- Z91.A9Caregiver's noncompliance with patient's other medical treatment and regimen
Questions about Z91.A3
- Is Z91.A3 a billable ICD-10-CM code?
- Yes. Z91.A3 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does Z91.A3 sit in the tabular list?
- Factors influencing health status and contact with health services (Z00-Z99), in the block Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).