2027 ICD-10-CM Diagnosis Code T45.515SAdverse effect of anticoagulants, sequela

ICD-10-CM Codes›S00–T88›T36-T50›T45

ICD-10-CM T45.515S
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

T45.515S is a billable ICD-10-CM diagnosis code for adverse effect of anticoagulants, 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 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 922 through 923. The code is not accepted as a principal diagnosis by the Medicare Code Editor and exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Poisoning/toxic effect/adverse effects/underdosing, sequela.

Code Identity

ICD-10-CM Code
T45.515S
Billable Status
Yes — Valid for Submission
Code Describes
Adverse effect of anticoagulants, sequela
Short Description
Adverse effect of anticoagulants, sequela
Same as the full description in the CMS dataset.
Parent Code
Adverse effect of anticoagulants

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
CategoryT45Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified
This CodeT45.515SAdverse effect of anticoagulants, sequela

Code EditsBilling

Medicare Code Editor checks that affect claim validity for T45.515S.

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.

Present on Admission (POA)Billing

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acenocoumarol adverse reaction
  • Adverse reaction to coumarin
  • Adverse reaction to danaparoid
  • Adverse reaction to indanedione
  • Anticoagulant adverse reaction
  • Coumarin necrosis
  • Dalteparin adverse reaction
  • Dermatosis caused by coumarin
  • Dermatosis resulting from anticoagulant therapy
  • Direct acting anticoagulant adverse reaction
  • Enoxaparin adverse reaction
  • Heparin adverse reaction
  • Heparinoid adverse reaction
  • Indirect acting anticoagulant adverse reaction
  • Pesticide adverse reaction
  • Phenindione adverse reaction
  • Rectal hemorrhage caused by apixaban
  • Rectal hemorrhage caused by drug
  • Tinzaparin adverse reaction
  • Transfusion reaction caused by toxic effect of anticoagulant
  • Warfarin adverse reaction
  • Warfarin monitoring status
  • Warfarin side effects

Coding GuidelinesGuidance

When coding an adverse effect of a drug that has been correctly prescribed and properly administered, assign the appropriate code for the nature of the adverse effect followed by the appropriate code for the adverse effect of the drug.

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 2027, published by CMS and the National Center for Health Statistics.

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to T45.515S: its own notes plus those printed at T45, block T36-T50, and Chapter 19. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances applies to 3,186 codes
  • adverse effect of correct substance properly administered
  • poisoning by overdose of substance
  • poisoning by wrong substance given or taken in error
  • underdosing by (inadvertently) (deliberately) taking less substance than prescribed or instructed

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances applies to 3,186 codes
  • toxic reaction to local anesthesia in pregnancy (O29.3-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances applies to 3,186 codes
  • abuse and dependence of psychoactive substances (F10-F19)
  • abuse of non-dependence-producing substances (F55.-)
  • immunodeficiency due to drugs (D84.821)
  • drug reaction and poisoning affecting newborn (P00-P96)
  • pathological drug intoxication (inebriation) (F10-F19)
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes

Code First

The underlying condition named in the note is sequenced before this code.

From Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances applies to 3,186 codes
  • for adverse effects, the nature of the adverse effect, such as:
  • adverse effect NOS (T88.7)
  • aspirin gastritis (K29.-)
  • blood disorders (D56-D76)
  • contact dermatitis (L23-L25)
  • dermatitis due to substances taken internally (L27.-)
  • nephropathy (N14.0-N14.2)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances applies to 3,186 codes
  • code(s) to specify:
  • manifestations of poisoning
  • underdosing or failure in dosage during medical and surgical care (Y63.6, Y63.8-Y63.9)
  • underdosing of medication regimen (Z91.12-, Z91.13-)
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • code to identify any retained foreign body, if applicable (Z18.-)

Notes

General instructions on how these codes are used.

From Block T36-T50 Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances applies to 3,186 codes
  • The drug giving rise to the adverse effect should be identified by use of codes from categories T36-T50 with fifth or sixth character 5.
From Chapter 19 (S00-T88) Injury, poisoning and certain other consequences of external causes applies to 41,187 codes
  • Use secondary code(s) from Chapter 20, External causes of morbidity, to indicate cause of injury. Codes within the T section that include the external cause do not require an additional external cause code
  • The chapter uses the S-section for coding different types of injuries related to single body regions and the T-section to cover injuries to unspecified body regions as well as poisoning and certain other consequences of external causes.

7th Character

Every code in the category takes a 7th character from the listed values, with the placeholder X filling any empty positions before it.

From T45 Poisoning by, adverse effect of and underdosing of primarily systemic and hematological agents, not elsewhere classified applies to 270 codes
  • The appropriate 7th character is to be added to each code from category T45
  • Ainitial encounter
  • Dsubsequent encounter
  • Ssequela this code

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name T45.515S, its category, or a range that includes it.

Use Additional Code 2

These codes say to use an additional code from the note, and T45.515S is one of the codes named.

  • D68.32 Hemorrhagic disorder due to extrinsic circulating anticoagulants
    code for adverse effect, if applicable, to identify drug (T45.515, T45.525) names T45.515, which includes this code
  • D75.82 Heparin induced thrombocytopenia (HIT)
    code, if applicable, for adverse effect of heparin (T45.515-) names T45.515-, which includes this code

Clinical ClassificationClinical

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

CCSR INJ075
Poisoning/toxic effect/adverse effects/underdosing, sequela
Default principal diagnosis: inpatient No · outpatient Yes

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
AcenocoumarinT45.511T45.512T45.513T45.514T45.515T45.516
AcenocoumarolT45.511T45.512T45.513T45.514T45.515T45.516
AnisindioneT45.511T45.512T45.513T45.514T45.515T45.516
Anticoagulant NECT45.511T45.512T45.513T45.514T45.515T45.516
BishydroxycoumarinT45.511T45.512T45.513T45.514T45.515T45.516
BromindioneT45.511T45.512T45.513T45.514T45.515T45.516
CoumadinT45.511T45.512T45.513T45.514T45.515T45.516
CoumarinT45.511T45.512T45.513T45.514T45.515T45.516
CoumetarolT45.511T45.512T45.513T45.514T45.515T45.516
CumetharolT45.511T45.512T45.513T45.514T45.515T45.516
DaniloneT45.511T45.512T45.513T45.514T45.515T45.516
Dicoumarol, dicoumarin, dicumarolT45.511T45.512T45.513T45.514T45.515T45.516
DiphenadioneT45.511T45.512T45.513T45.514T45.515T45.516
Drotrecogin alfaT45.511T45.512T45.513T45.514T45.515T45.516
Enoxaparin (sodium)T45.511T45.512T45.513T45.514T45.515T45.516
Ethyl::biscoumacetateT45.511T45.512T45.513T45.514T45.515T45.516
Ethylidene::dicoumarinT45.511T45.512T45.513T45.514T45.515T45.516
Ethylidene::dicoumarolT45.511T45.512T45.513T45.514T45.515T45.516
FluindioneT45.511T45.512T45.513T45.514T45.515T45.516
Heparin (sodium)T45.511T45.512T45.513T45.514T45.515T45.516
Heparin-fractionT45.511T45.512T45.513T45.514T45.515T45.516
Heparinoid (systemic)T45.511T45.512T45.513T45.514T45.515T45.516
Indandione (derivatives)T45.511T45.512T45.513T45.514T45.515T45.516
Indendione (derivatives)T45.511T45.512T45.513T45.514T45.515T45.516
Inhibitor::prothrombin synthesisT45.511T45.512T45.513T45.514T45.515T45.516
NicoumaloneT45.511T45.512T45.513T45.514T45.515T45.516
PanwarfinT45.511T45.512T45.513T45.514T45.515T45.516
PhenindioneT45.511T45.512T45.513T45.514T45.515T45.516
PhenprocoumonT45.511T45.512T45.513T45.514T45.515T45.516
Prothrombin::synthesis inhibitorT45.511T45.512T45.513T45.514T45.515T45.516
SintromT45.511T45.512T45.513T45.514T45.515T45.516
TioclomarolT45.511T45.512T45.513T45.514T45.515T45.516
WarfarinT45.511T45.512T45.513T45.514T45.515T45.516
Warfarin::sodiumT45.511T45.512T45.513T45.514T45.515T45.516
XigrisT45.511T45.512T45.513T45.514T45.515T45.516
ZovantT45.511T45.512T45.513T45.514T45.515T45.516

Patient EducationClinical

Drug Reactions

Most of the time, medicines make our lives better. They reduce aches and pains, fight infections, and control problems such as high blood pressure or diabetes. But medicines can also cause unwanted reactions, such as drug interactions, side effects, and allergies.

The full article covers:

  • What is a drug interaction?
  • What are side effects?
  • What are drug allergies?
  • How can I stay safe when taking medicines?

Read the full article at MedlinePlus

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

Convert T45.515S to ICD-9-CMHistory

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

ICD-9-CM
909.5 Lte efct advrs efct drug
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
E934.2 Adv eff anticoagulants
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About T45.515SOverview

What is the ICD-10 code for adverse effect of anticoagulants, sequela?

The ICD-10-CM code for adverse effect of anticoagulants, sequela is T45.515S (sometimes written as T45515S). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is T45.515S (Adverse effect of anticoagulants) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report adverse effect of anticoagulants, sequela on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What does the 7th character S in T45.515S mean?

The final character S makes this a sequela code: it reports a lingering problem that remains after the adverse effect of anticoagulants itself has resolved, not the original event.

What MS-DRG does T45.515S group to?

On inpatient claims, adverse effect of anticoagulants, sequela maps to MS-DRG 923, 922, with relative weights from 0.9980 to 1.6248 depending on complications. Higher weights mean higher Medicare reimbursement.

Can T45.515S be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because adverse effect of anticoagulants, sequela describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.