2026 ICD-10-CM Diagnosis Code T41.296AUnderdosing of other general anesthetics, initial encounter

ICD-10-CM Codes›S00–T88›T36-T50›T41

ICD-10-CM T41.296A
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T41.296A is a billable ICD-10-CM diagnosis code for underdosing of other general anesthetics, 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
T41.296A
Billable Status
Yes — Valid for Submission
Code Describes
Underdosing of other general anesthetics, initial encounter
Short Description
Underdosing of other general anesthetics, initial encounter
Same as the full description in the CMS dataset.
Parent Code
T41.296
Underdosing of other general anesthetics

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
CategoryT41Poisoning by, adverse effect of and underdosing of anesthetics and therapeutic gases
This CodeT41.296AUnderdosing of other general anesthetics, initial encounter

Code EditsBilling

Medicare Code Editor checks that affect claim validity for T41.296A.

Unacceptable principal diagnosis
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 anesthetics and therapeutic gases (T41). 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

  • Ketamine

    a cyclohexanone derivative used for induction of anesthesia. its mechanism of action is not well understood, but ketamine can block nmda receptors (receptors, n-methyl-d-aspartate) and may interact with sigma receptors.

  • Propanidid

    an intravenous anesthetic that has been used for rapid induction of anesthesia and for maintenance of anesthesia of short duration. (from martindale, the extra pharmacopoeia, 30th ed, p918)

  • Propofol

    an intravenous anesthetic agent which has the advantage of a very rapid onset after infusion or bolus injection plus a very short recovery period of a couple of minutes. (from smith and reynard, textbook of pharmacology, 1992, 1st ed, p206). propofol has been used as anticonvulsants and antiemetics.

  • Propofol Infusion Syndrome

    rare and often fatal drug complication which affects patients undergoing long-term treatment with high doses of propofol. it is characterized by metabolic acidosis; hyperlipidemia; rhabdomyolysis; cardiovascular circulatory collapse; cardiac failure; and kidney failure.

  • Tiletamine

    proposed anesthetic with possible anticonvulsant and sedative properties.

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
CyclopropaneT41.291T41.292T41.293T41.294T41.295T41.296
DisoprofolT41.291T41.292T41.293T41.294T41.295T41.296
KetamineT41.291T41.292T41.293T41.294T41.295T41.296
MinaxoloneT41.291T41.292T41.293T41.294T41.295T41.296
Oxybate sodiumT41.291T41.292T41.293T41.294T41.295T41.296
PropanididT41.291T41.292T41.293T41.294T41.295T41.296
PropofolT41.291T41.292T41.293T41.294T41.295T41.296
TiletamineT41.291T41.292T41.293T41.294T41.295T41.296
Tribromoethanol, rectalT41.291T41.292T41.293T41.294T41.295T41.296

Patient EducationClinical

Anesthesia

Anesthesia is the use of medicines, called anesthetics, to prevent pain during surgery and other medical procedures. Medicine may be given by injection, inhalation, topical lotion, spray, eye drops, or a skin patch.

The full article covers:

  • What is anesthesia?
  • What is anesthesia used for?
  • What are the types of anesthesia?
  • What are the risks of anesthesia?

Read the full article at MedlinePlus

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

Convert T41.296A 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 T41.296AOverview

Is T41.296A (Underdosing of other general anesthetics) a billable code?

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

What does the 7th character A in T41.296A mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for underdosing of other general anesthetics, such as an emergency visit or first evaluation.

Can T41.296A be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because underdosing of other general anesthetics, 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.