2024 ICD-10-CM Diagnosis Code T46.3X6A

Underdosing of coronary vasodilators, initial encounter

ICD-10-CM Code:
T46.3X6A
ICD-10 Code for:
Underdosing of coronary vasodilators, initial encounter
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Not chronic
Code Navigator:

Code Classification

  • Injury, poisoning and certain other consequences of external causes
    (S00–T88)
    • Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances
      (T36-T50)
      • Poisoning by, adverse effect of and underdosing of agents primarily affecting the cardiovascular system
        (T46)

T46.3X6A is a billable diagnosis code used to specify a medical diagnosis of underdosing of coronary vasodilators, initial encounter. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

This code describes a circumstance which influences the patient's health status but not a current illness or injury. The code is unacceptable as a principal diagnosis.

T46.3X6A is an initial encounter code, includes a 7th character and should be used while the patient is receiving active treatment for a condition like underdosing of coronary vasodilators. According to ICD-10-CM Guidelines an "initial encounter" doesn't necessarily means "initial visit". The 7th character should be used when the patient is undergoing active treatment regardless if new or different providers saw the patient over the course of a treatment. The appropriate 7th character codes should also be used even if the patient delayed seeking treatment for a condition.

Clinical Classification

Clinical Information

  • 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.

Coding Guidelines

Underdosing refers to taking less of a medication than is prescribed by a provider or a manufacturer's instruction. Codes for underdosing should never be assigned as principal or first-listed codes. If a patient has a relapse or exacerbation of the medical condition for which the drug is prescribed because of the reduction in dose, then the medical condition itself should be coded.

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 aplicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10-CM Code Edits are applicable to this code:

  • Unacceptable principal diagnosis - 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.

Convert T46.3X6A to ICD-9-CM

  • ICD-9-CM Code: -
    No Map Flag -

Table of Drugs and Chemicals

The parent code T46.3X6 of the current diagnosis code is referenced in the Table of Drugs and Chemicals, this table contains a classification of drugs, industrial solvents, corrosive gases, noxious plants, pesticides, and other toxic agents.

According to ICD-10-CM coding guidelines it is advised to do not code directly from the Table of Drugs and Chemicals, instead always refer back to the Tabular List when doing the initial coding. Each substance in the table is assigned a code according to the poisoning classification and external causes of adverse effects. It is important to use as many codes as necessary to specify all reported drugs, medicinal or chemical substances. If the same diagnosis code describes the causative agent for more than one adverse reaction, poisoning, toxic effect or underdosing, utilize the code only once.

Substance Poisoning
Accidental
(unintentional)
Poisoning
Accidental
(self-harm)
Poisoning
Assault
Poisoning
Undetermined
Adverse
effect
Underdosing
AmikhellineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
BendazolT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
BenziodaroneT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
CarbocromenT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
ChromonarT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Coronary vasodilator NECT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
CromonarT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
DiisopropylamineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
DilazepT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
DimoxylineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
DioxylineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
DipyridamoleT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
EfloxateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Eritrityl tetranitrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Erythrityl tetranitrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Erythrol tetranitrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
EtafenoneT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
FenalcomineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
FluorosolT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
HeptaminolT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
HexadilineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
HexadylamineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
HexobendineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
IpriflavoneT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Isoamyl nitriteT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Isosorbide dinitrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Itramin tosilateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
KhellinT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
KhellosideT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
MolsidomineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
NicorandilT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Nitrate, organicT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Nitrite, amyl (medicinal) (vapor)T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Nitroglycerin, nitro-glycerol (medicinal)T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Nitroglycerin, nitro-glycerol (medicinal)
  »nonmedicinal
T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Nitroglycerin, nitro-glycerol (medicinal)
  »nonmedicinal
    »fumes
T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Octyl nitriteT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Organonitrate NECT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
OxyfedrineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
PentaerythritolT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Pentaerythritol
  »chloral
T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Pentaerythritol
  »tetranitrate NEC
T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Pentaerythrityl tetranitrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
PentrinatT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
PerhexileneT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Perhexiline (maleate)T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
PeritrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
PiridoxilateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
PrenylamineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
PropatylnitrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Sorbide nitrateT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Sweet niter spiritT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
TenitramineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
TerodilineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
TrapidilT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
TrinitrineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Trolnitrate (phosphate)T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
VasodilatorT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Vasodilator
  »coronary NEC
T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
Vasodilator
  »peripheral NEC
T46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6
VisnadineT46.3X1T46.3X2T46.3X3T46.3X4T46.3X5T46.3X6

Patient Education


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:

  • Knowing your medicines. When you get a prescription, ask the name of the medicine and check to make sure that the pharmacy gave you the right medicine. Make sure that you understand how often you should take the medicine and how long you should take it.
  • Keeping a list of medicines.
    • Write down all of the medicines that you are taking, including the names of your medicines, how much you take, and when you take them. Make sure to include any over-the-counter medicines, vitamins, supplements, and herbs that you take.
    • List the medicines that you are allergic to or that have caused you problems in the past.
    • Take this list with you every time you see a health care provider.
  • Reading medicine labels and following the directions. Don't just rely on your memory - read the medication label every time. Be especially careful when giving medicines to children.
  • Asking questions. If you don't know the answers to these questions, ask your health care provider or pharmacist:
    • Why am I taking this medicine?
    • What are the common side effects?
    • What should I do if I have side effects?
    • When should I stop this medicine?
    • Can I take this medicine with the other medicines and supplements on my list?
    • Do I need to avoid certain foods or alcohol while taking this medicine?

Food and Drug Administration


[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.

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.