2026 ICD-10-CM Diagnosis Code T50.1X5SAdverse effect of loop [high-ceiling] diuretics, sequela

ICD-10-CM CodesS00–T88T36-T50T50

ICD-10-CM T50.1X5S
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T50.1X5S is a billable ICD-10-CM diagnosis code for adverse effect of loop [high-ceiling] diuretics, 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 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
T50.1X5S
Billable Status
Yes — Valid for Submission
Code Describes
Adverse effect of loop [high-ceiling] diuretics, sequela
Short Description
Adverse effect of loop [high-ceiling] diuretics, sequela
Same as the full description in the CMS dataset.
Parent Code
Adverse effect of loop [high-ceiling] diuretics

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
CategoryT50Poisoning by, adverse effect of and underdosing of diuretics and other and unspecified drugs, medicaments and biological substances
This CodeT50.1X5SAdverse effect of loop [high-ceiling] diuretics, sequela

Code EditsBilling

Medicare Code Editor checks that affect claim validity for T50.1X5S.

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

T50.1X5S 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.

  • Adverse reaction to saluretic agent
  • Bumetanide adverse reaction
  • Ethacrynic acid adverse reaction
  • Furosemide adverse reaction
  • Loop diuretic adverse reaction
  • Pesticide adverse reaction
  • Piretanide adverse reaction
  • Sulfonamide diuretic adverse reaction
  • Torasemide adverse reaction

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 diuretics and other and unspecified drugs, medicaments and biological substances (T50). 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 INJ075
Poisoning/toxic effect/adverse effects/underdosing, sequela
Default principal diagnosis: inpatient No · outpatient Yes

Clinical InformationClinical

  • Bumetanide

    a sulfamyl diuretic.
  • Sodium Potassium Chloride Symporter Inhibitors

    agents that inhibit sodium-potassium-chloride symporters which are concentrated in the thick ascending limb at the junction of the loop of henle and kidney tubules, distal. they act as diuretics. excess use is associated with hypokalemia and hyperglycemia.
  • Solute Carrier Family 12, Member 1

    na-k-cl transporter in the ascending limb of loop of henle. it mediates active reabsorption of sodium chloride and is inhibited by loop diuretics such as furosemide; and bumetanide. mutations in the gene encoding slc12a1 are associated with a bartter syndrome.
  • Solute Carrier Family 12, Member 2

    na-k-cl transporter ubiquitously expressed. it plays a key role in salt secretion in epithelial cells and cell volume regulation in nonepithelial cells.
  • Ethacrynic Acid

    a compound that inhibits symport of sodium, potassium, and chloride primarily in the ascending limb of henle, but also in the proximal and distal tubules. this pharmacological action results in excretion of these ions, increased urinary output, and reduction in extracellular fluid. this compound has been classified as a loop or high ceiling diuretic.
  • Furosemide

    a benzoic-sulfonamide-furan. it is a diuretic with fast onset and short duration that is used for edema and chronic renal insufficiency.
  • Ticrynafen

    a novel diuretic with uricosuric action. it has been proposed as an antihypertensive 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.

SubstanceAccidentalSelf-harmAssaultUndeter­minedAdverse
Effect
Under­dosing
BumetanideT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
EdecrinT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
Etacrynate sodiumT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
Etacrynic acidT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
Ethacrynic acidT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
EtozolinT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
FrusemideT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
FurosemideT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
LasixT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
Lyovac Sodium EdecrinT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
PiretanideT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
TicrynafenT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6
Tienilic acidT50.1X1T50.1X2T50.1X3T50.1X4T50.1X5T50.1X6

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 T50.1X5S 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
E944.4 Adv eff diuretics NEC
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T50.1X5SOverview

Is T50.1X5S (Adverse effect of loop [high-ceiling] diuretics) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report adverse effect of loop [high-ceiling] diuretics, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character S in T50.1X5S mean?

The final character S makes this a sequela code: it reports a lingering problem that remains after the adverse effect of loop [high-ceiling] diuretics itself has resolved, not the original event.

What MS-DRG does T50.1X5S group to?

On inpatient claims, adverse effect of loop [high-ceiling] diuretics, sequela maps to MS-DRG 922, 923, with relative weights from 1.0177 to 1.7494 depending on complications. Higher weights mean higher Medicare reimbursement.

Can T50.1X5S be a principal diagnosis?

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

Is T50.1X5S 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 adverse effect of loop [high-ceiling] diuretics, sequela on inpatient claims.

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.