2026 ICD-10-CM Diagnosis Code T47.1X6AUnderdosing of other antacids and anti-gastric-secretion drugs, initial encounter

ICD-10-CM CodesS00–T88T36-T50T47

ICD-10-CM T47.1X6A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T47.1X6A is a billable ICD-10-CM diagnosis code for underdosing of other antacids and anti-gastric-secretion drugs, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The code is not accepted as a principal diagnosis by the Medicare Code Editor. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Underdosing of drugs and medicaments, initial encounter.

Code Identity

ICD-10-CM Code
T47.1X6A
Billable Status
Yes — Valid for Submission
Code Describes
Underdosing of other antacids and anti-gastric-secretion drugs, initial encounter
Short Description
Underdosing of antacids and anti-gstrc-sec drugs, init
Parent Code
Underdosing of other antacids and anti-gastric-secretion drugs

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT36-T50Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances
CategoryT47Poisoning by, adverse effect of and underdosing of agents primarily affecting the gastrointestinal system
This CodeT47.1X6AUnderdosing of other antacids and anti-gastric-secretion drugs, initial encounter

Code EditsBilling

Medicare Code Editor checks that affect claim validity for T47.1X6A.

There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Coding GuidelinesGuidance

Underdosing refers to taking less of a medication than is prescribed by a provider or a manufacturer's instruction. Codes for underdosing should never be assigned as principal or first-listed codes. If a patient has a relapse or exacerbation of the medical condition for which the drug is prescribed because of the reduction in dose, then the medical condition itself should be coded.

The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of agents primarily affecting the gastrointestinal system (T47). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INJ029
Underdosing of drugs and medicaments, initial encounter
Default principal diagnosis: inpatient No · outpatient No

Clinical InformationClinical

  • Burimamide

    an antagonist of histamine that appears to block both h2 and h3 histamine receptors. it has been used in the treatment of ulcers.
  • Carbenoxolone

    an agent derived from licorice root. it is used for the treatment of digestive tract ulcers, especially in the stomach. antidiuretic side effects are frequent, but otherwise the drug is low in toxicity.
  • Enprostil

    a synthetic pge2 analog that has an inhibitory effect on gastric acid secretion, a mucoprotective effect, and a postprandial lowering effect on gastrin. it has been shown to be efficient and safe in the treatment of gastroduodenal ulcers.
  • Metiamide

    a histamine h2 receptor antagonist that is used as an anti-ulcer agent.
  • Misoprostol

    a synthetic analog of natural prostaglandin e1. it produces a dose-related inhibition of gastric acid and pepsin secretion, and enhances mucosal resistance to injury. it is an effective anti-ulcer agent and also has oxytocic properties.
  • Omeprazole

    a 4-methoxy-3,5-dimethylpyridyl, 5-methoxybenzimidazole derivative of timoprazole that is used in the therapy of stomach ulcers and zollinger-ellison syndrome. the drug inhibits an h(+)-k(+)-exchanging atpase which is found in gastric parietal cells.
  • Pirenzepine

    an antimuscarinic agent that inhibits gastric secretion at lower doses than are required to affect gastrointestinal motility, salivary, central nervous system, cardiovascular, ocular, and urinary function. it promotes the healing of duodenal ulcers and due to its cytoprotective action is beneficial in the prevention of duodenal ulcer recurrence. it also potentiates the effect of other antiulcer agents such as cimetidine and ranitidine. it is generally well tolerated by patients.
  • Proglumide

    a drug that exerts an inhibitory effect on gastric secretion and reduces gastrointestinal motility. it is used clinically in the drug therapy of gastrointestinal ulcers.
  • Simethicone

    a poly(dimethylsiloxane) which is a polymer of 200-350 units of dimethylsiloxane, along with added silica gel. it is used as an antiflatulent, surfactant, and ointment base.
  • Sucralfate

    a basic aluminum complex of sulfated sucrose.

Table of Drugs and ChemicalsClinical

Substances in the Table of Drugs and Chemicals that reference this code family. Always confirm in the Tabular List before coding.

SubstanceAccidentalSelf-harmAssaultUndeter­minedAdverse
Effect
Under­dosing
Alexitol sodiumT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
AlgeldrateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
AlmagateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
AlmasilateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
AloglutamolT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
Antacid NECT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
Anti-gastric-secretion drug NECT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
BenexateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
BurimamideT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
CarbenoxoloneT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
CetraxateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
Chalk, precipitatedT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
Dihydroxyaluminum aminoacetateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
Dihydroxyaluminum sodium carbonateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
DimethiconeT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
DimeticoneT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
EnprostilT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
HydrotalciteT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
MagaldrateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
Magnesia magmaT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
MethylpolysiloxaneT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
MetiamideT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
Milk of magnesiaT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
MisoprostolT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
OmeprazoleT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
OrnoprostilT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
PepstatinT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
PirenzepineT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
ProglumideT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
RolaidsT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
RosaprostolT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
SimaldrateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
SimethiconeT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
SucralfateT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6
SulglicotideT47.1X1T47.1X2T47.1X3T47.1X4T47.1X5T47.1X6

Patient EducationClinical

Medication Errors

Medicines treat infectious diseases, prevent problems from chronic diseases, and ease pain. But medicines can also cause harmful reactions if not used correctly. Errors can happen in the hospital, at the health care provider's office, at the pharmacy, or at home. You can help prevent errors by:

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert T47.1X6A to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
No Map There is no ICD-9 equivalent for this code.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T47.1X6AOverview

Is T47.1X6A a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report underdosing of other antacids and anti-gastric-secretion drugs, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T47.1X6A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for underdosing of other antacids and anti-gastric-secretion drugs, such as an emergency visit or first evaluation.

Can T47.1X6A be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because underdosing of other antacids and anti-gastric-secretion drugs, initial encounter describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.