2026 ICD-10-CM Diagnosis Code T44.4X1APoisoning by predominantly alpha-adrenoreceptor agonists, accidental (unintentional), initial encounter
T44.4X1A is a billable ICD-10-CM diagnosis code for poisoning by predominantly alpha-adrenoreceptor agonists, accidental (unintentional), 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) and groups to MS-DRG 917 through 918. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under External cause codes: intent of injury, accidental/unintentional; External cause codes: poisoning by drug; and Poisoning by drugs, initial encounter.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Accidental metaraminol overdose
- Accidental metaraminol poisoning
- Accidental poisoning by adrenergics
- Accidental poisoning by norepinephrine
- Alpha-adrenoceptor agonist overdose
- Alpha-adrenoceptor agonist poisoning
- Central alpha-2 adrenergic receptor agonist overdose
- Central alpha-2 adrenergic receptor agonist poisoning
- Metaraminol overdose
- Poisoning by metaraminol
- Poisoning caused by norepinephrine
- Vasopressor drug overdose
Coding GuidelinesGuidance
When coding a poisoning or reaction to the improper use of a medication (e.g., overdose, wrong substance given or taken in error, wrong route of administration), first assign the appropriate code from categories T36-T50. The poisoning codes have an associated intent as their 5th or 6th character (accidental, intentional self-harm, assault and undetermined). If the intent of the poisoning is unknown or unspecified, code the intent as accidental intent. The undetermined intent is only for use if the documentation in the record specifies that the intent cannot be determined. Use additional code(s) for all manifestations of poisonings.
The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of drugs primarily affecting the autonomic nervous system (T44). 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
Etilefrine
a phenylephrine-related beta-1 adrenergic and alpha adrenergic agonist used as a cardiotonic and antihypotensive agent.Metaraminol
a sympathomimetic agent that acts predominantly at alpha-1 adrenergic receptors. it has been used primarily as a vasoconstrictor in the treatment of hypotension.Methoxamine
an alpha-1 adrenergic agonist that causes prolonged peripheral vasoconstriction.Norepinephrine
precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the locus ceruleus. it is also found in plants and is used pharmacologically as a sympathomimetic.Norepinephrine Plasma Membrane Transport Proteins
sodium chloride-dependent neurotransmitter symporters located primarily on the plasma membrane of noradrenergic neurons. they remove norepinephrine from the extracellular space by high affinity reuptake into presynaptic terminals. the norepinephrine transporter regulates signal amplitude and duration at noradrenergic synapses and is the target of adrenergic uptake inhibitors.Phenylethanolamine N-Methyltransferase
a methyltransferase that catalyzes the reaction of s-adenosyl-l-methionine and phenylethanolamine to yield s-adenosyl-l-homocysteine and n-methylphenylethanolamine. it can act on various phenylethanolamines and converts norepinephrine into epinephrine. (from enzyme nomenclature, 1992) ec 2.1.1.28.Receptors, Adrenergic
cell-surface proteins that bind epinephrine and/or norepinephrine with high affinity and trigger intracellular changes. the two major classes of adrenergic receptors, alpha and beta, were originally discriminated based on their cellular actions but now are distinguished by their relative affinity for characteristic synthetic ligands. adrenergic receptors may also be classified according to the subtypes of g-proteins with which they bind; this scheme does not respect the alpha-beta distinction.Phenylephrine
an alpha-1 adrenergic agonist used as a mydriatic, nasal decongestant, and cardiotonic agent.
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
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 T44.4X1A to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T44.4X1AOverview
Is T44.4X1A a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by predominantly alpha-adrenoreceptor agonists, accidental (unintentional), initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T44.4X1A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for poisoning by predominantly alpha-adrenoreceptor agonists, accidental (unintentional), such as an emergency visit or first evaluation.
What MS-DRG does T44.4X1A group to?
When poisoning by predominantly alpha-adrenoreceptor agonists, accidental (unintentional), initial encounter is the principal diagnosis on an inpatient stay, it groups to MS-DRG 917, 918, with relative weights from 0.8571 to 1.5684 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of T44.4X1A?
Under the General Equivalence Mappings, poisoning by predominantly alpha-adrenoreceptor agonists, accidental (unintentional), initial encounter converts to ICD-9-CM 971.2 (poison-sympathomimetics) and E855.5 (acc poison-adrenergics). The mapping is approximate, so confirm the match fits the documentation.
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.
