2026 ICD-10-CM Diagnosis Code T41.1X6AUnderdosing of intravenous anesthetics, initial encounter
T41.1X6A is a billable ICD-10-CM diagnosis code for underdosing of intravenous 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
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for T41.1X6A.
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.
Clinical InformationClinical
Etomidate
imidazole derivative anesthetic and hypnotic with little effect on blood gases, ventilation, or the cardiovascular system. it has been proposed as an induction anesthetic.Methohexital
an intravenous anesthetic with a short duration of action that may be used for induction of anesthesia.Thiamylal
a barbiturate that is administered intravenously for the production of complete anesthesia of short duration, for the induction of general anesthesia, or for inducing a hypnotic state. (from martindale, the extra pharmacopoeia, 30th ed, p919)
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.
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 T41.1X6A to ICD-9-CMHistory
Code HistoryHistory
Questions About T41.1X6AOverview
Is T41.1X6A (Underdosing of intravenous anesthetics) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report underdosing of intravenous anesthetics, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T41.1X6A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for underdosing of intravenous anesthetics, such as an emergency visit or first evaluation.
Can T41.1X6A be a principal diagnosis?
No. The Medicare Code Editor rejects this code as a principal diagnosis because underdosing of intravenous 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.
