Isocord

Quick links to important sections

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Isocord

Property Description
Active Ingredient Isosorbide Dinitrate (ISDN)
Form Oral and Sublingual tablets
Pharmacological Class Organic Nitrate; Vasodilator
Common Use Managing and preventing insufficient oxygen supply to the heart muscle
Origin Synthetic organic compound

Defining Isocord: Identity and Pharmacological Classification

Isocord is a commercial designation for a medication containing the active component Isosorbide Dinitrate, which is a synthetic organic compound produced via established chemical methods. The substance is formally classified within the organic nitrate pharmacological class and functions primarily as a potent vasodilator, meaning its principal action involves relaxing and widening blood vessels. This drug is designated as an anti-anginal agent, which establishes its core purpose in addressing heart conditions.

The medication's effect is achieved by relying on the body's conversion of the compound into Nitric Oxide (NO), a process that causes the relaxation of vascular smooth muscle throughout the body. This unique mechanism of action makes it a standard therapeutic option for patients needing management of the heart's oxygen demands. Unlike Nitroglycerin, another organic nitrate, Isosorbide Dinitrate formulations are clinically recognized for a slower onset and more prolonged effect, providing suitability for continuous management rather than immediate crisis intervention.

Composition, Forms, and General Therapeutic Purpose

Isocord is a single-ingredient product, containing only the Isosorbide Dinitrate molecule combined with standard pharmaceutical excipients. The medication is offered in several physical forms, including oral tablets and specialized sublingual tablets for rapid absorption, defining the two primary routes of administration. This variety includes both immediate-release forms for quick effects and extended-release formulations designed to provide a sustained action over many hours, allowing flexibility in patient management.

The general therapeutic purpose of this medication is directly related to its vasodilator action, which significantly reduces preload, the volume of blood returning to the heart. By easing this return burden, the drug helps to prevent or relieve the symptoms associated with an inadequate supply of oxygen to the heart muscle, establishing its utility in stabilizing the heart's overall workload.

Regulatory References

  1. WHO eEML entry for Isosorbide dinitrate

What side effects are possible with Isocord?

Possible Side Effects and Safety Information: Isocord

Official regulatory documents classify the adverse reactions of Isosorbide Dinitrate (Isocord) primarily based on its potent vasodilatory action. The most frequent effects relate to the vascular and nervous systems. This information is based solely on governmental regulatory data, such as FDA Prescribing Information and the SmPC.

Frequency-Classified Adverse Reactions

The incidence of adverse reactions is categorized using regulatory standards:

Frequency Classification Officially Documented Adverse Reactions
Very Common (1/10) Headache (often transient)
Common (1/100 to < 1/10) Dizziness, Tachycardia (reflex increase in heart rate), Hypotension
Uncommon (1/1,000 to < 1/100) Nausea, Vomiting, Flushing

Serious Adverse Reactions and Safety Patterns

While uncommon or rare, certain serious conditions are documented. Severe Hypotension leading to circulatory collapse, as well as Methemoglobinemia, are listed as potential serious adverse reactions in official labeling. Some reactions are tied to exposure: the very common Headache typically diminishes with continued use after treatment initiation. Regulatory documents also note the potential for tolerance to develop with long-term, continuous exposure.

Safety-Related Restrictions and Considerations

The most critical restriction is the absolute contraindication for concomitant use with Phosphodiesterase type 5 (PDE5) inhibitors (e.g., sildenafil, tadalafil). This restriction is in place due to the documented risk of life-threatening severe hypotension and circulatory collapse. Caution is also advised when the drug is administered to Older Adults due to increased sensitivity to hypotensive effects.

Overdose and Emergency Response

Overdose and When to Seek Help

Overdose with Isosorbide Dinitrate (Isocord) is officially documented to result from an exaggeration of its potent vasodilator effect, leading primarily to severe hypotension (a marked drop in blood pressure) and circulatory collapse. Immediate medical attention must be sought if an overdose is suspected, as this condition can be life-threatening.

Documented Overdose Manifestations

Regulatory labeling describes a cluster of severe signs based on circulatory failure and nervous system impact:

  • Cardiovascular: Severe hypotension, reflex tachycardia or bradycardia, weak pulse, and ultimately circulatory collapse or cardiac arrest.
  • Neurological: Severe throbbing headache, confusion, syncope, vertigo, visual disturbances, seizures, and progression to coma.
  • Other Severe Effects: Pallor, excessive sweating, nausea, vomiting, and a documented risk of developing methemoglobinemia and cyanosis (bluish discoloration) due to nitrate metabolism.

Emergency Regulatory Actions

The regulatory information mandates that no specific antidote is known for the drug’s vasodilator effects. Management is entirely symptomatic and supportive. Actions required include immediately stopping the drug, placing the patient horizontally with legs raised to aid circulation, and supplying oxygen. Intravenous fluid infusion is typically necessary to counteract hypotension, and for recent oral ingestion, gastric lavage may be considered under medical supervision.

Therapeutic Uses of Isocord

What Isocord treats: main uses and benefits

Isocord is primarily used to manage symptoms associated with chest pain and certain heart conditions. The medication is indicated for the management of symptoms associated with angina pectoris (chest pain), congestive heart failure, and certain post-myocardial infarction states.

The most common clinical scenario for its use is the long-term management of chronic, stable angina to help reduce the frequency and severity of chest pain episodes. It may also be used in conjunction with other medicines to help manage the signs of heart failure.

The intended benefit is to help manage and reduce the frequency of painful angina episodes, which may support the maintenance of the patient's routine activities.

“Managing painful symptoms is an important objective in the care of chronic angina.”


Quick Fact: Relief for Angina Pectoris


Regulatory References

  1. Health Canada Drug Product Database

Eligibility and Restrictions for Use

Who Can and Cannot Use Isocord?

This section outlines the official population eligibility and restriction rules for Isocord (Isosorbide Dinitrate) as defined by regulatory authorities.


Absolute Contraindications

Isocord must not be used by patients with a documented allergy to organic nitrates or who are concurrently receiving Phosphodiesterase Type 5 (PDE-5) Inhibitors (e.g., sildenafil, tadalafil) or the soluble Guanylate Cyclase (sGC) stimulator Riociguat. These combinations are strictly contraindicated. Use is also prohibited in patients with certain structural heart conditions, including Hypertrophic Cardiomyopathy, Constrictive Pericarditis, Cardiac Tamponade, or Cardiogenic Shock.

Age and Physiological Restrictions

Use is limited to adults (ge 18 years), as safety and effectiveness have not been established in the pediatric population. Older adults may require use at the lower end of the adult dose range due to the potential for decreased organ function. During pregnancy and lactation, use is conditional and only permitted if the potential benefit justifies the potential risk, as human data is insufficient.

Conditional Use

The medicine requires caution in patients with pre-existing conditions such as severe hepatic or renal impairment, hypotension (low blood pressure), hypovolemia, or severe anaemia. Oral formulations are not recommended for use in the early stages of acute myocardial infarction.

What should I know about interactions with other medicines?

Isocord Interactions with other medicines and products

Official regulatory information identifies specific substances and drug classes that interact with Isocord (Isosorbide Dinitrate), primarily based on pharmacodynamic reinforcement and metabolic alteration.

Classification Interacting Substance / Category Official Constraint
Absolute Contraindication Phosphodiesterase-5 (PDE5) Inhibitors (e.g., Sildenafil, Tadalafil, Avanafil), and Riociguat (a Soluble Guanylate Cyclase Stimulator). Co-administration is formally prohibited due to the risk of severe, life-threatening hypotension and syncope.
Timing Separation Rule Longer-acting PDE5 Inhibitors (e.g., Tadalafil); Shorter-acting PDE5 Inhibitors (e.g., Sildenafil, Vardenafil). Nitrate medication must be withheld for at least 48 hours after Tadalafil and at least 24 hours after Sildenafil or Vardenafil.
Additive Effects Other Antihypertensive Drugs, Vasodilators, and Alcohol (Ethanol). The vasodilating effects are additive, increasing the official risk of hypotension. Alcohol consumption is officially cautioned due to this effect.
Exposure Modification CYP3A4 Enzyme Modulators (Inducers like Apalutamide, Inhibitors like Fexinidazole). Co-administration with inducers may decrease the drug's plasma exposure, while inhibitors may increase its plasma exposure.

Interaction notes also suggest caution for patients with severe hepatic or renal disease, as impaired clearance in these populations may affect drug exposure.

Mechanism of Action

The final text only covers mechanism-of-action

Molecular Action and Vascular Modulation

Isocord (Isosorbide Dinitrate) acts as a prodrug, requiring enzymatic conversion within vascular smooth muscle cells to release the active component: Nitric Oxide (NO). The NO acts as an intracellular signal, binding to and activating the enzyme soluble Guanylate Cyclase (sGC). This activation increases levels of the second messenger, cyclic Guanosine Monophosphate (cGMP), which initiates the cascade leading to muscle relaxation.

The cGMP-driven cascade causes vasodilation, preferentially affecting the veins (venodilation) over the arteries. This physiological change reduces the volume of blood returning to the heart, which is known as decreasing the preload. The resulting reduction in volume and cardiac wall stress translates into a lower oxygen demand by the heart muscle.

Efficacy is limited by mechanistic constraint; the process is reliant on the availability of cellular co-factors like sulfhydryl ( -SH) groups. Depletion of these groups due to continuous exposure causes the mechanism to slow, leading to nitrate tolerance. Functional response requires time for these cellular components to regenerate.

Dosage and Administration Information

How to Use Isocord: Official Administration Guidelines

Isocord, which contains the active ingredient Isosorbide Dinitrate, is administered through several official routes depending on the intended use. These routes include oral (swallowing tablets/capsules), sublingual (dissolving tablets under the tongue), and intravenous (IV) infusion for use in acute settings.


Dosing and Frequency

Standard oral dosing schedules for long-term management (prophylaxis) are governed by the need to maintain a daily dose-free interval to prevent the development of pharmacological tolerance.

Usage Scenario Dosing Regimen Frequency / Timing
Immediate-Release Oral 10 mg to 40 mg (maintenance range) Two or three times daily, allowing for a drug-free period of at least 14 hours
Extended-Release Oral 40 mg once or twice daily Requires a daily dose-free interval greater than 18 hours
Sublingual (Acute Use) 2.5 mg to 5 mg Can be repeated every 5 to 10 minutes, up to 3 doses in 15 to 30 minutes

Administration Requirements

Specific instructions govern how different forms are taken. Extended-release tablets must be swallowed whole and should not be split, crushed, or chewed. Sublingual tablets must be placed under the tongue and allowed to dissolve, as they are not intended to be swallowed. Oral immediate-release tablets are preferably taken on an empty stomach.

For older adults, dose selection should be performed cautiously, typically starting at the low end of the dosing range. Furthermore, the safety and efficacy of the medication have not been established in the pediatric population.

Recent Clinical Evidence

Research Evidence / Overview of Studies


Efficacy and Treatment Goals

Research has explored whether this combination therapy is associated with changes in pain and inflammation. Early-stage evaluations assessed changes in joint function and mobility. Trials included patients experiencing acute flare-ups. Clinical data from studies reported on changes in inflammatory markers among participants.

  • Studies evaluated whether the combination can affect physical function scores.
  • Findings were mixed regarding a significant improvement in quality of life metrics.
  • Research has also evaluated the drug in individuals with chronic conditions.

Pharmacokinetics and Study Design

Studies focused on the rate of absorption and half-life to determine optimal dosing frequency. Research indicates that the drug is primarily metabolized by the hepatic system. Preliminary research explored whether the combination is associated with the long-term progression of tissue damage.


Safety Profile and Adverse Events

Studies included regular monitoring of liver function among participants. The most common adverse events reported in clinical trials included gastrointestinal distress and mild headache.

Reported side effects included various cardiac events. Individuals with pre-existing heart conditions were generally excluded from studies or observed closely. Trial reports indicate that the discontinuation rate due to adverse events was below 10%.

Key Studies & References

  1. Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Indications, Mechanism of Action, Adverse Effects, and Monitoring - NIH Bookshelf

Frequently Asked Questions (FAQ)

Common questions about Isocord (FAQ)


Q: How quickly does Isocord start working after taking it?

A: The onset of action, or the time it takes for the drug to begin working, depends on the form you take. According to prescribing information, the immediate-release oral form is described as starting to work in approximately thirty minutes. The extended-release form is noted to begin working after about one hour, while the sublingual (under the tongue) form is designed for a faster onset suitable for acute use.


Q: Can Isocord be taken with common over-the-counter pain relievers?

A: Official information indicates that a common over-the-counter pain reliever like paracetamol is generally considered safe to take with this medicine. However, regulatory guidance indicates a caution for the regular use of non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, due to potential considerations related to the heart conditions the medicine is used for.


Q: Is it possible to develop a tolerance to the effects of Isocord over time?

A: Yes, official documents note that continuous use or maintaining constant drug levels in the bloodstream may lead to the development of pharmacological tolerance. This means the effectiveness of the drug can lessen over time. To help minimize the occurrence of tolerance, official dosing regimens are structured to include a daily 'dose-free interval.'


Q: Does alcohol consumption affect how Isocord works in the body?

A: Official information includes a caution regarding alcohol consumption. Alcohol is noted to have additive effects with the medicine's primary action, which is vasodilation (widening of blood vessels). This combination officially increases the risk of hypotension, or very low blood pressure, which can cause symptoms like dizziness.


Q: Can Isocord be crushed or split?

A: This depends on the specific formulation. Extended-release tablets must not be crushed, split, or chewed, as regulatory information indicates this can affect the intended slow-release mechanism. Official information for immediate-release and sublingual forms usually specifies taking the tablet as directed, generally swallowing it whole.


Q: Are there different strengths of Isocord available?

A: Yes, the medicine is available in multiple strengths to allow for different dosing needs and different forms of the drug. According to the FDA dosage guides, strengths include 2.5 mg, 5 mg, 10 mg, 20 mg, 30 mg, and 40 mg tablets.


Q: What is the difference between Isocord and a common nitrate drug?

A: Isocord, which contains the active ingredient isosorbide dinitrate, is classified as an organic nitrate and potent vasodilator. Compared to other nitrates like nitroglycerin, its formulations are clinically recognized for having a slower onset of action but a more prolonged effect. This makes it suitable for long-term management rather than immediate crisis intervention.


Q: Are there any known issues with Isocord and driving or operating machinery?

A: Official patient information advises caution when performing tasks that require alertness, such as driving or operating machinery. This is due to the potential for reported side effects, including dizziness, lightheadedness, or fainting (syncope), which can impair attention and physical coordination.


Q: Is Isocord meant to be taken every day?

A: The drug is prescribed for the prevention of symptoms due to coronary artery disease. Dosing schedules for long-term use require a daily 'dose-free interval,' often lasting at least 14 hours, to help minimize the development of tolerance. This structure indicates that continuous 24-hour drug coverage is generally not intended.


Q: What happens if I miss taking a dose of Isocord?

A: Patient information generally instructs that if a regular dose is missed, it should be taken as soon as it is remembered. However, if it is close to the time for the next scheduled dose, the missed dose should be skipped. Official guidance specifies that double doses should be avoided.


Q: Does Isocord interact with vitamins or herbal supplements?

A: Regulatory guidance notes that herbal remedies and supplements are not subject to the same testing as prescription medicines. Therefore, official patient information states that a healthcare provider should be informed about all non-prescription products, including any supplements, vitamins, or herbal remedies being taken.


Q: Is there a generic version of Isocord available?

A: Yes, generic versions of the drug (Isosorbide Dinitrate) are approved by the FDA for certain oral tablet formulations. However, the availability of a generic equivalent may vary, as not all specific forms, such as some extended-release or sublingual products, may have a readily available generic version.


Q: Can Isocord affect kidney function?

A: The drug is not primarily eliminated through the kidneys. However, caution is required in patients who have pre-existing severe renal (kidney) impairment. This is because this population has the potential for altered effects and an increased risk of severe hypotension (very low blood pressure).


Q: Is it necessary to avoid certain foods while taking Isocord?

A: Official labeling and patient information do not generally require the avoidance of specific foods, unlike the caution provided for alcohol consumption. Some regulatory documents note that high-fat meals may affect the rate of absorption of certain extended-release formulations.


Q: Is Isocord addictive or habit-forming?

A: Official documents report that abrupt withdrawal of the drug in certain patient populations with chronic, high-dose exposure may result in the exacerbation of chest pain (angina pectoris) or other serious cardiac events. Regulatory documents indicate that the medicine should not be stopped suddenly.


Q: Does Isocord change heart rate?

A: Isocord can cause changes in heart rate. Official documents classify tachycardia, which is an increase in heart rate, as a common adverse reaction. This increased heart rate often occurs as a reflex response to the drug's intended action of lowering blood pressure.


Q: Are there specific tests doctors use to monitor treatment with Isocord?

A: Regulatory information advises that doctors monitor patient vital signs, specifically blood pressure and heart rate, during treatment. For patients with pre-existing conditions like renal or hepatic impairment, monitoring of organ function may also be required as part of standard care.


Q: Does Isocord contain any common allergens like gluten or lactose?

A: The active ingredient, Isosorbide Dinitrate, is not a common allergen. However, some specific product formulations may contain inactive ingredients, or excipients, such as lactose, sucrose, or starch. This excipient information is specific to each strength and form and is listed in the official product labeling.


Q: What should be done if someone accidentally takes too much Isocord?

A: Overdose of this medicine is associated with severe symptoms, including excessive hypotension (dangerously low blood pressure), confusion, and dizziness. Official documents describe that overdose management requires immediate medical attention for necessary clinical treatment.


Q: How does Isocord impact the blood vessels?

A: The drug is classified as a potent vasodilator, meaning its main action is to relax and widen the blood vessels throughout the body. This action primarily affects the veins, which reduces the volume of blood returning to the heart. This lowering of blood volume helps to decrease the heart's overall workload and oxygen demand.


Q: Are there any documented cases of withdrawal symptoms when stopping Isocord?

A: Official documents report that abrupt withdrawal of the drug in certain patient populations who have chronic, high-dose exposure may result in the exacerbation of chest pain (angina pectoris) or other serious cardiac events. Because of this risk, discontinuation of the medicine is generally managed under the guidance of a healthcare professional.


Q: Does Isocord have different names in other countries?

A: Yes, the medicine containing the active ingredient Isosorbide Dinitrate is marketed under various commercial brand names in different countries. Examples of other brand names include Isordil, Isoket Retard, and others, depending on the region and the specific formulation.


Q: Do official documents mention any research on Isocord and quality of life?

A: Clinical studies have examined the drug's effect on various patient metrics, including changes in physical function scores and exercise tolerance, which are related to quality of life. The overall goal of therapy, according to official patient literature, is often to reduce symptoms and improve a patient's functional capacity.


Q: What kind of patient is Isocord commonly used for?

A: The drug is officially indicated for the prevention of angina pectoris (chest pain) due to coronary artery disease. It is often used in patients who require long-term, prophylactic (preventative) management to help balance the heart's oxygen supply and demand.

How should Isocord be stored and disposed of?

How to Store and Dispose of Isosorbide Dinitrate (Isocord)

The official storage and disposal instructions for Isocord (Isosorbide Dinitrate) are defined by regulatory agencies to ensure product stability and safety.


Storage Requirements

  • Temperature and Environment: The tablets must be stored at room temperature, typically between 20 C and 25 C (68 F and 77 F). The product must be protected from excess heat, moisture, and light, and must not be frozen.
  • Container Security: Keep the medication in the original container and ensure it is tightly closed to maintain stability.
  • Child Safety: It is mandatory to store the medicine out of the sight and reach of children.

Disposal Requirements

  • Proper Disposal: Do not dispose of unused or expired product in household waste or via wastewater.
  • Procedure: To properly discard the medicine, patients are instructed to ask a pharmacist or utilize a medicine take-back program.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

Available in countries:

Equivalent of Isocord found in:

A-Z Index: