I1A.0 – Resistant hypertension

ICD-10-CM 2027 diagnosis code · Hypertensive diseases

Billable code

ICD-10-CM code I1A.0
Code
I1A.0 (claims format: I1A0)
Description
Resistant hypertension
Billable
Yes – valid for HIPAA-covered transactions
Valid for
Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter
9. Diseases of the circulatory system (I00-I99)
Block
I10-I1A Hypertensive diseases
Parent codes
I1A

Notes for I1A.0

Applicable to:
  • Apparent treatment resistant hypertension
  • Treatment resistant hypertension
  • True resistant hypertension
Code first:
  • specific type of existing hypertension, if known, such as:
  • essential hypertension (I10)
  • secondary hypertension (I15.-)

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

Block I10-I1A

Excludes1 (not coded here):
  • neonatal hypertension (P29.2)
  • primary pulmonary hypertension (I27.0)
Excludes2 (not included here):
  • hypertensive disease complicating pregnancy, childbirth and the puerperium (O10-O11, O13-O16)
Use additional code:
  • code to identify:
  • exposure to environmental tobacco smoke (Z77.22)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Index terms for I1A.0

Entries in the ICD-10-CM alphabetic index that lead to this code:

Frequently asked questions

What is ICD-10 code I1A.0?

I1A.0 is the ICD-10-CM code for resistant hypertension, in the block I10-I1A (Hypertensive diseases).

Is I1A.0 a billable code?

Yes. I1A.0 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does I1A.0 belong to?

It belongs to category I1A – Other hypertension.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.