2026 ICD-10-CM Diagnosis Code T46.3X5SAdverse effect of coronary vasodilators, sequela
T46.3X5S is a billable ICD-10-CM diagnosis code for adverse effect of coronary vasodilators, 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
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for T46.3X5S.
Present on Admission (POA)Billing
T46.3X5S 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 coronary vasodilator
- Adverse reaction to platelet aggregation inhibitor
- Adverse reaction to smooth muscle relaxant
- Adverse reaction to terodiline
- Dipyridamole adverse reaction
- Glyceryl trinitrate adverse reaction
- Glyceryl trinitrate spray adverse reaction
- Isosorbide dinitrate adverse reaction
- Isosorbide mononitrate adverse reaction
- Modified release GTN adverse reaction
- Modified release isosorbide dinitrate adverse reaction
- Modified release isosorbide mononitrate adverse reaction
- Nicorandil adverse reaction
- Nitrate vasodilator adverse reaction
- Nitrite-induced flushing
- Oral glyceryl trinitrate adverse reaction
- Oral isosorbide dinitrate adverse reaction
- Parenteral glyceryl trinitrate adverse reaction
- Parenteral isosorbide dinitrate adverse reaction
- Pentaerythritol tetranitrate adverse reaction
- Prenylamine adverse reaction
- Transdermal glyceryl trinitrate 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 agents primarily affecting the cardiovascular system (T46). 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
Chromonar
a coronary vasodilator agent.Dilazep
coronary vasodilator with some antiarrhythmic activity.Aspirin, Dipyridamole Drug Combination
a drug combination of aspirin and dipyridamole that functions as a platelet aggregation inhibitor, used to prevent thrombosis and stroke in transient ischemic attack patients.Dipyridamole
a phosphodiesterase inhibitor that blocks uptake and metabolism of adenosine by erythrocytes and vascular endothelial cells. dipyridamole also potentiates the antiaggregating action of prostacyclin. (from ama drug evaluations annual, 1994, p752)Erythrityl Tetranitrate
a vasodilator with general properties similar to nitroglycerin. (from martindale, the extra pharmacopoeia, 30th ed, p1020)Heptaminol
an amino alcohol that has been used as a myocardial stimulant and vasodilator and to relieve bronchospasm. its most common therapeutic use is in orthostatic hypotension. the mechanism of heptaminol's therapeutic actions is not well understood although it has been suggested to affect catecholamine release or calcium metabolism.Hexobendine
a potent vasoactive agent that dilates cerebral and coronary arteries, but slightly constricts femoral arteries, without any effects on heart rate, blood pressure or cardiac output.Isosorbide Dinitrate
a vasodilator used in the treatment of angina pectoris. its actions are similar to nitroglycerin but with a slower onset of action.Khellin
a vasodilator that also has bronchodilatory action. it has been employed in the treatment of angina pectoris, in the treatment of asthma, and in conjunction with ultraviolet light a, has been tried in the treatment of vitiligo. (from martindale, the extra pharmacopoeia, 30th ed, p1024)Molsidomine
a morpholinyl sydnone imine ethyl ester, having a nitrogen in place of the keto oxygen. it acts as nitric oxide donors and is a vasodilator that has been used in angina pectoris.Nicorandil
a derivative of the niacinamide that is structurally combined with an organic nitrate. it is a potassium-channel opener that causes vasodilatation of arterioles and large coronary arteries. its nitrate-like properties produce venous vasodilation through stimulation of guanylate cyclase.Oxyfedrine
a drug used in the treatment of angina pectoris, heart failure, conduction defects, and myocardial infarction. it is a partial agonist at beta adrenergic receptors and acts as a coronary vasodilator and cardiotonic agent.Prenylamine
a drug formerly used in the treatment of angina pectoris but superseded by less hazardous drugs. prenylamine depletes myocardial catecholamine stores and has some calcium channel blocking activity. (from martindale, the extra pharmacopoeia, 30th ed, p1406)Trapidil
a coronary vasodilator 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
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 T46.3X5S to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T46.3X5SOverview
Is T46.3X5S (Adverse effect of coronary vasodilators) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report adverse effect of coronary vasodilators, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in T46.3X5S mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the adverse effect of coronary vasodilators itself has resolved, not the original event.
What MS-DRG does T46.3X5S group to?
On inpatient claims, adverse effect of coronary vasodilators, 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 T46.3X5S be a principal diagnosis?
No. The Medicare Code Editor rejects this code as a principal diagnosis because adverse effect of coronary vasodilators, sequela describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.
Is T46.3X5S 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 coronary vasodilators, 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.
