Question: Someone told me that there are new ICD-10-CM codes effective in April, but I thought new codes only came out in October. Which is correct? Georgia Subscriber Answer: It is true that some new ICD-10-CM codes become effective April 1, but historically new options became effective only once a year on Oct. 1. In September 2021, the Centers for Medicare and Medicaid Services (CMS) and the Centers for Disease Control and Prevention (CDC) decided to update ICD-10-CM codes twice a year, with new codes being effective on April 1 as well as the traditional effective date of October 1. This year, ICD-10-CM introduced 42 new codes, deleted seven, and revised one, effective April 1, 2023. Many of the new codes describe social determinants of health (SDoH) and cluster in Chapters 19, 20, and 21. The new codes in Chapter 19 describe consequences of external causes, including codes in the T74.- family with descriptions of confirmed abuse, and the T76.- family, with descriptions of suspected abuse. Changes in chapter 20 involve an expansion of Y07.- (Perpetrator of assault, maltreatment and neglect) code group. Chapter 21 includes new codes in the Persons with potential health hazards related to socioeconomic and psychosocial circumstances (Z55-Z65) section. Two of the new codes in particular could easily come into play in the lab setting, with physicians ordering tests for therapeutic drugs: Helpful hint: For Z55.6, the inclusion terms provided are “difficulty understanding health related information,” “difficulty understanding medication instructions,” and “problem completing medical forms.” For the full 2023 ICD-10-CM April 2023 addenda, go to https://ftp.cdc.gov/pub/Health_Statistics/NCHS/Publications/ ICD10CM/April-1-2023-Update/ and download the zip file labeled icd10cm-addendum-April 1, 2023.