2026 ICD-10-CM Diagnosis Code T45.7X1SPoisoning by anticoagulant antagonists, vitamin K and other coagulants, accidental (unintentional), sequela
T45.7X1S is a billable ICD-10-CM diagnosis code for poisoning by anticoagulant antagonists, vitamin K and other coagulants, accidental (unintentional), sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 922 through 923. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Poisoning/toxic effect/adverse effects/underdosing, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
T45.7X1S is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Accidental protamine overdose
- Accidental protamine poisoning
- Accidental vitamin K and/or vitamin K derivative overdose
- Accidental vitamin K poisoning
- Antidote overdose
- Coagulant overdose
- Poisoning by coagulant
- Poisoning by hexadimethrine
- Poisoning by vitamin K
- Poisoning caused by protamine
- Protamine overdose
- Vitamin K and/or vitamin K derivative 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 primarily systemic and hematological agents, not elsewhere classified (T45). 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
Ethamsylate
benzenesulfonate derivative used as a systemic hemostatic.Hypoprothrombinemias
absence or reduced levels of prothrombin in the blood.Prothrombin
a plasma protein that is the inactive precursor of thrombin. it is converted to thrombin by a prothrombin activator complex consisting of factor xa, factor v, phospholipid, and calcium ions. deficiency of prothrombin leads to hypoprothrombinemia.Prothrombin Time
clotting time of plasma recalcified in the presence of excess tissue thromboplastin. factors measured are fibrinogen; prothrombin; factor v; factor vii; and factor x. it is used for monitoring anticoagulant therapy with coumarins.Thromboplastin
constituent composed of protein and phospholipid that is widely distributed in many tissues. it serves as a cofactor with factor viia to activate factor x in the extrinsic pathway of blood coagulation.Anticoagulants
agents that prevent blood clotting.Antithrombins
endogenous factors and drugs that directly inhibit the action of thrombin, usually by blocking its enzymatic activity. they are distinguished from indirect thrombin inhibitors, such as heparin, which act by enhancing the inhibitory effects of antithrombins.Carboxypeptidase B2
a carboxypeptidase that removes c-terminal lysine or arginine from peptides and proteins. carboxypeptidase b2 (cpb2) is released into the circulation as a proenzyme which is activated by the thrombin-thrombomodulin complex. activated cpb2 is involved in modulating a variety of processes by cleaving and inactivating various circulating proteins and peptides that are its substrates including fibrin; kinins; and anaphylatoxins.Factor VIIIa
activated form of factor viii. the b-domain of factor viii is proteolytically cleaved by thrombin to form factor viiia. factor viiia exists as a non-covalent dimer in a metal-linked (probably calcium) complex and functions as a cofactor in the enzymatic activation of factor x by factor ixa. factor viiia is similar in structure and generation to factor va.Receptors, Thrombin
a family of proteinase-activated receptors that are specific for thrombin. they are found primarily on platelets and on endothelial cells. activation of thrombin receptors occurs through the proteolytic action of thrombin, which cleaves the n-terminal peptide from the receptor to reveal a new n-terminal peptide that is a cryptic ligand for the receptor. the receptors signal through heterotrimeric gtp-binding proteins. small synthetic peptides that contain the unmasked n-terminal peptide sequence can also activate the receptor in the absence of proteolytic activity.Thrombin
an enzyme formed from prothrombin that converts fibrinogen to fibrin.Thrombin Time
clotting time of plasma mixed with a thrombin solution. it is a measure of the conversion of fibrinogen to fibrin, which is prolonged by afibrinogenemia, abnormal fibrinogen, or the presence of inhibitory substances, e.g., fibrin-fibrinogen degradation products, or heparin. batroxobin, a thrombin-like enzyme unaffected by the presence of heparin, may be used in place of thrombin.Factor VIII
factor viii of blood coagulation. antihemophilic factor that is part of the factor viii/von willebrand factor complex. factor viii is produced in the liver and acts in the intrinsic pathway of blood coagulation. it serves as a cofactor in factor x activation and this action is markedly enhanced by small amounts of thrombin.Factor XI
stable blood coagulation factor involved in the intrinsic pathway. the activated form xia activates factor ix to ixa. deficiency of factor xi is often called hemophilia c.Partial Thromboplastin Time
the time required for the appearance of fibrin strands following the mixing of plasma with phospholipid platelet substitute (e.g., crude cephalins, soybean phosphatides). it is a test of the intrinsic pathway (factors viii, ix, xi, and xii) and the common pathway (fibrinogen, prothrombin, factors v and x) of blood coagulation. it is used as a screening test and to monitor heparin therapy.
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 T45.7X1S to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T45.7X1SOverview
Is T45.7X1S a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by anticoagulant antagonists, vitamin K and other coagulants, accidental (unintentional), sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in T45.7X1S mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the poisoning by anticoagulant antagonists, vitamin K and other coagulants, accidental (unintentional) itself has resolved, not the original event.
What MS-DRG does T45.7X1S group to?
When poisoning by anticoagulant antagonists, vitamin K and other coagulants, accidental (unintentional), sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 922, 923, with relative weights from 1.0177 to 1.7494 depending on complications. Higher weights mean higher Medicare reimbursement.
Is T45.7X1S exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for poisoning by anticoagulant antagonists, vitamin K and other coagulants, accidental (unintentional), sequela on inpatient claims.
What is the ICD-9 equivalent of T45.7X1S?
Under the General Equivalence Mappings, poisoning by anticoagulant antagonists, vitamin K and other coagulants, accidental (unintentional), sequela converts to ICD-9-CM 909.0 (late eff drug poisoning) and E929.2 (late eff acc poisoning). 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.
