ICD-10-CM > Z00-Z99 > Z77-Z99 > Z91 > Z91.A > Z91.A2 Z91.A2 Caregiver's intentional underdosing of patient's medication regimen Non-Billable/Non-Specific Code First underdosing of medication (T36-T50) with fifth or sixth character 6 Codes Z91.A20Caregiver's intentional underdosing of patient's medication regimen due to financial hardshipZ91.A28Caregiver's intentional underdosing of medication regimen for other reason