Medicine guide

Isosorbide Dinitrate

5 mg · Tablet

Prescription only
Nitrate Vasodilator

Active substance: Isosorbide Dinitrate
Used in: Heart, blood pressure and circulation
Made by: AvPAK
Source: Official label

Quoted from the official source. Not yet reviewed by Mediclarum — the leaflet in your pack is authoritative.

At a glance

Quoted from the official label · 2026-02-10

What it is

Nitrate Vasodilator

Used for

Isosorbide dinitrate tablets are indicated for the prevention of angina pectoris due to coronary artery disease.

The label’s usual adult dose

The usual starting dose of isosorbide dinitrate is 5 mg to 20 mg, two or three times daily.

Full directions ↓

Do not take it if

Isosorbide dinitrate is contraindicated in patients who are allergic to isosorbide dinitrate or any of its other ingredients.

All warnings ↓

Good to know

Prescription only
FDA enforcement reports list no ongoing recall, and none from the last two years, for this product code · checked 2026-10-02

54other products contain Isosorbide Dinitrate — compare makers, forms and strengths

Every line above is selected, not written, from the official label. Nothing is reworded. DailyMed

What it is for

Isosorbide dinitrate tablets are indicated for the prevention of angina pectoris due to coronary artery disease.
The onset of action of immediate-release oral isosorbide dinitrate is not sufficiently rapid for this product to be useful in aborting an acute anginal episode.

From the official label · 2026-02-10 · DailyMed

How it works

From this product’s own US prescribing label.

The principal pharmacological action of isosorbide dinitrate is relaxation of vascular smooth muscle and consequent dilatation of peripheral arteries and veins, especially the latter.
Dilatation of the veins promotes peripheral pooling of blood and decreases venous return to the heart, thereby reducing left ventricular end-diastolic pressure and pulmonary capillary wedge pressure (preload).

How the body breaks it down

Absorption of isosorbide dinitrate after oral dosing is nearly complete, but bioavailability is highly variable (10% to 90%), with extensive first-pass metabolism in the liver.

Quoted from the prescribing label, sections “Mechanism of Action” and “Pharmacokinetics”. DailyMed · 2026-02-10

Do not take it if

Isosorbide dinitrate is contraindicated in patients who are allergic to isosorbide dinitrate or any of its other ingredients.
Do not use isosorbide dinitrate in patients who are taking certain drugs for erectile dysfunction (phosphodiesterase inhibitors), such as sildenafil, tadalafil, or vardenafil.
Concomitant use can cause severe hypotension, syncope, or myocardial ischemia.
Do not use isosorbide dinitrate in patients who are taking the soluble guanylate cyclase stimulator riociguat.
Concomitant use can cause hypotension.

Quoted from the official label, section “Contraindications”.

How to take it

These directions are for this exact strength and form. Another one is different.

As noted under " CLINICAL PHARMACOLOGY ," multiple-dose studies with isosorbide dinitrate and other nitrates have shown that maintenance of continuous 24-hour plasma levels results in refractory tolerance.
Every dosing regimen for isosorbide dinitrate tablets must provide a daily dose-free interval to minimize the development of this tolerance.
With immediate-release isosorbide dinitrate, it appears that one daily dose-free interval must be at least 14 hours long.
As also noted under " CLINICAL PHARMACOLOGY ," the effects of the second and later doses have been smaller and shorter-lasting than the effects of the first.
Large controlled studies with other nitrates suggest that no dosing regimen with isosorbide dinitrate tablets should be expected to provide more than about 12 hours of continuous anti-anginal efficacy per day.
As with all titratable drugs, it is important to administer the minimum dose which produces the desired clinical effect.
The usual starting dose of isosorbide dinitrate is 5 mg to 20 mg, two or three times daily.
For maintenance therapy, 10 mg to 40 mg, two or three times daily is recommended.
Some patients may require higher doses.
A daily dose-free interval of at least 14 hours is advisable to minimize tolerance.
The optimal interval will vary with the individual patient, dose and regimen.

Quoted from the official label, section “Dosage & Administration”.

Other warnings

Amplification of the vasodilatory effects of isosorbide dinitrate by sildenafil can result in severe hypotension.
The time course and dose dependence of this interaction have not been studied.
Appropriate supportive care has not been studied, but it seems reasonable to treat this as a nitrate overdose, with elevation of the extremities and with central volume expansion.
The benefits of immediate-release oral isosorbide dinitrate in patients with acute myocardial infarction or congestive heart failure have not been established.
If one elects to use isosorbide dinitrate in these conditions, careful clinical or hemodynamic monitoring must be used to
avoid the hazards of hypotension and tachycardia.
Because the effects of oral isosorbide dinitrate are so difficult to terminate rapidly, this formulation is not recommended in these settings.
Severe hypotension, particularly with upright posture, may occur with even small doses of isosorbide dinitrate.
This drug should therefore be used with caution in patients who may be volume depleted or who, for whatever reason, are already hypotensive.
Hypotension induced by isosorbide dinitrate may be accompanied by paradoxical bradycardia and increased angina pectoris.
Nitrate therapy may aggravate the angina caused by hypertrophic cardiomyopathy.
As tolerance to isosorbide dinitrate develops, the effect of sublingual nitroglycerin on exercise tolerance, although still observable, is somewhat blunted.
Some clinical trials in angina patients have provided nitroglycerin for about 12 continuous hours of every 24-hour day.
During the daily dose-free interval in some of these trials, anginal attacks have been more easily provoked than before treatment, and patients have demonstrated hemodynamic rebound and decreased exercise tolerance.
The importance of these observations to the routine, clinical use of immediate-release oral isosorbide dinitrate is not known.
In industrial workers who have had long-term exposure to unknown (presumably high) doses of organic nitrates, tolerance clearly occurs.
Chest pain, acute myocardial infarction, and even sudden death have occurred during temporary withdrawal of nitrates from these workers, demonstrating the existence of true physical dependence.
Information for Patients Patients should be told that the anti-anginal efficacy of isosorbide dinitrate is strongly related to its dosing regimen, so the prescribed schedule of dosing should be followed carefully.
Drug Interactions The vasodilating effects of isosorbide dinitrate may be additive with those of other vasodilators.
Carcinogenesis and Mutagenesis and Impairment of Fertility No long-term studies in animals have been performed to evaluate the carcinogenic potential of isosorbide dinitrate.
In a modified two-litter reproduction study, there was no remarkable gross pathology and no altered fertility or gestation among rats fed isosorbide dinitrate at 25 or 100 mg/kg/day.
Pregnancy Category C At oral doses 35 and 150 times the maximum recommended human daily dose, isosorbide dinitrate has been shown to cause a dose-related increase in embryotoxicity (increase in mummified pups) in rabbits.
Nursing Mothers It is not known whether isosorbide dinitrate is excreted in human milk.
Pediatric Use Safety and effectiveness in pediatric patients have not been established.
Geriatric Use Clinical studies of isosorbide dinitrate did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

Quoted from the official label, section “Warnings”.

Pregnancy and breastfeeding

Category C At oral doses 35 and 150 times the maximum recommended human daily dose, isosorbide dinitrate has been shown to cause a dose-related increase in embryotoxicity (increase in mummified pups) in rabbits.
There are no adequate, well-controlled studies in pregnant women.
Isosorbide dinitrate should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
It is not known whether isosorbide dinitrate is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when isosorbide dinitrate is administered to a nursing woman.

Quoted from the official label, section “OTC — Pregnancy or Breast Feeding”.

Other medicines

The vasodilating effects of isosorbide dinitrate may be additive with those of other vasodilators.
Alcohol, in particular, has been found to exhibit additive effects of this variety.
Concomitant use of isosorbide dinitrate with phosphodiesterase inhibitors in any form is contraindicated (see CONTRAINDICATIONS ).
Concomitant use of isosorbide dinitrate with riociguat, a soluble guanylate cyclase stimulator, is contraindicated (see CONTRAINDICATIONS ).

Quoted from the official label, section “Drug Interactions”.

If you take too much

In an emergency, call your local emergency number or a poison control centre.

Hemodynamic Effects The ill effects of isosorbide dinitrate overdose are generally the results of isosorbide dinitrate's capacity to induce vasodilatation, venous pooling, reduced cardiac output, and hypotension.
These hemodynamic changes may have protean manifestations, including increased intracranial pressure, with any or all of persistent throbbing headache, confusion, and moderate fever; vertigo; palpitations; visual disturbances; nausea and vomiting (possibly with colic and even bloody diarrhea); syncope (especially in the upright posture); air hunger and dyspnea, later followed by reduced ventilatory effort; diaphoresis, with the skin either flushed or cold and clammy; heart block and bradycardia, paralysis; coma; seizures; and death.
Laboratory determinations of serum levels of isosorbide dinitrate and its metabolites are not widely available, and such determinations have, in any event, no established role in the management of isosorbide dinitrate overdose.
There are no data suggesting what dose of isosorbide dinitrate is likely to be life-threatening in humans.
In rats, the median acute lethal dose (LD 50 ) was found to be 1100 mg/kg.
No data are available to suggest physiological maneuvers ( e.g. , maneuvers to change the pH of the urine) that might accelerate elimination of isosorbide dinitrate and its active metabolites.
Similarly, it is not known which, if any, of these substances can usefully be removed from the body by hemodialysis.
No specific antagonist to the vasodilator effects of isosorbide dinitrate is known, and no intervention has been subject to controlled studies as a therapy for isosorbide dinitrate overdose.
Because the hypotension associated with isosorbide dinitrate overdose is the result of venodilatation and arterial hypovolemia, prudent therapy in this situation should be directed toward increase in central fluid volume.
Passive elevation of the patient's legs may be sufficient, but intravenous infusion of normal saline or similar fluid may also be necessary.
The use of epinephrine or other arterial vasoconstrictors in this setting is likely to do more harm than good.
In patients with renal disease or congestive heart failure, therapy resulting in central volume expansion is not without hazard.
Treatment of isosorbide dinitrate overdosage in these patients may be subtle and difficult, and invasive monitoring may be required.
Methemoglobinemia Nitrate ions liberated during metabolism of isosorbide dinitrate can oxidize hemoglobin into methemoglobin.
Even in patients totally without cytochrome b 5 reductase activity, however, and even assuming that the nitrate moieties of isosorbide dinitrate are quantitatively applied to oxidation of hemoglobin, about 1 mg/kg of isosorbide dinitrate should be required before any of these patients manifests clinically significant (≥10%) methemoglobinemia.
In patients with normal reductase function, significant production of methemoglobin should require even larger doses of isosorbide dinitrate.
In one study in which 36 patients received 2 to 4 weeks of continuous nitroglycerin therapy at 3.1 to 4.4 mg/hr (equivalent, in total administered dose of nitrate ions, to 4.8 to 6.9 mg of bioavailable isosorbide dinitrate per hour), the average methemoglobin level measured was 0.2%; this was comparable to that observed in parallel patients who received placebo.
Notwithstanding these observations, there are case reports of significant methemoglobinemia in association with moderate overdoses of organic nitrates.
None of the affected patients had been thought to be unusually susceptible.
Methemoglobin levels are available from most clinical laboratories.
The diagnosis should be suspected in patients who exhibit signs of impaired oxygen delivery despite adequate cardiac output and adequate arterial pO 2 .
Classically, methemoglobinemic blood is described as chocolate brown, without color change on exposure to air.
When methemoglobinemia is diagnosed, the treatment of choice is methylene blue, 1 to 2 mg/kg intravenously.

Quoted from the official label, section “Overdosage”.

Use in children

Safety and effectiveness in pediatric patients have not been established.

Quoted from the official label, section “Pediatric Use”.

Use in older people

Clinical studies of isosorbide dinitrate did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.
Other reported clinical experience has not identified differences in responses between the elderly and younger patients.
In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

Quoted from the official label, section “Geriatric Use”.

Side effects

Adverse reactions to isosorbide dinitrate are generally dose-related, and almost all of these reactions are the result of isosorbide dinitrate's activity as a vasodilator.
Headache, which may be severe, is the most commonly reported side effect.
Headache may be recurrent with each daily dose, especially at higher doses.
Transient episodes of lightheadedness, occasionally related to blood pressure changes, may also occur.
Hypotension occurs infrequently, but in some patients it may be severe enough to warrant discontinuation of therapy.
Syncope, crescendo angina, and rebound hypertension have been reported but are uncommon.
Extremely rarely, ordinary doses of organic nitrates have caused methemoglobinemia in normal-seeming patients.
Methemoglobinemia is so infrequent at these doses that further discussion of its diagnosis and treatment is deferred (see OVERDOSAGE ).
Data are not available to allow estimation of the frequency of adverse reactions during treatment with isosorbide dinitrate tablets.
To report SUSPECTED ADVERSE REACTIONS contact AvKARE at 1-855-361-3993; email drugsafety@avkare.com ; or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .

Quoted from the official label, section “Adverse Reactions”.

What to discuss with your doctor

Patients should be told that the anti-anginal efficacy of isosorbide dinitrate is strongly related to its dosing regimen, so the prescribed schedule of dosing should be followed carefully.
In particular, daily headaches sometimes accompany treatment with isosorbide dinitrate.
In patients who get these headaches, the headaches are a marker of the activity of the drug.
Patients should resist the temptation to
avoid headaches by altering the schedule of their treatment with isosorbide dinitrate, since loss of headache may be associated with simultaneous loss of anti-anginal efficacy.
Aspirin and/or acetaminophen, on the other hand, often successfully relieve isosorbide dinitrate-induced headaches with no deleterious effect on isosorbide dinitrate's anti-anginal efficacy.
Treatment with isosorbide dinitrate may be associated with lightheadedness on standing, especially just after rising from a recumbent or seated position.
This effect may be more frequent in patients who have also consumed alcohol.

Quoted from the official label, section “Patient Counseling Information”.

What it looks like and how it is packed

Isosorbide dinitrate tablets, USP are available as follows:
5 mg oral, white, round, bisected tablets, debossed with "PAR 020" on one side and plain on the other side.
NDC 50268-447-15 (10 tablets per card, 5 cards per carton). 10 mg oral, white, round, bisected tablets, debossed with "PAR 021" on one side and plain on the other side.
NDC 50268-448-15 (10 tablets per card, 5 cards per carton). 20 mg oral, green, round, bisected tablets, debossed with "PAR 022" on one side and plain on the other side.
NDC 50268-449-15 (10 tablets per card, 5 cards per carton). 30 mg oral, blue, round, bisected tablets, debossed with "PAR 009" on one side and plain on the other side.
Dispensed in Unit Dose Package.
For Institutional Use Only.
Store at room temperature, approximately 25°C (77°F).
Protect from light.
Keep bottles tightly closed.
Dispense in a light-resistant, tight container.

Quoted from the official label, section “How Supplied”.

What is in it

Isosorbide dinitrate, an organic nitrate, is a vasodilator with effects on both arteries and veins.
The chemical name for isosorbide dinitrate is 1,4:3,6-dianhydro-D-glucitol 2, 5-dinitrate.
The compound has the following structural formula: C 6 H 8 N 2 0 8 MW
236.14 Isosorbide dinitrate is a white, crystalline, odorless compound which is stable in air and in solution, has a melting point of 70°C and has an optical rotation of +134° (c=1.0, alcohol, 20°C).
Isosorbide dinitrate is freely soluble in organic solvents such as acetone, alcohol, and ether, but is only sparingly soluble in water.
Isosorbide dinitrate tablets are available for oral administration as 5 mg, 10 mg, 20 mg, or 30 mg tablets.
Each tablet contains the following inactive ingredients:
lactose anhydrous, magnesium stearate, microcrystalline cellulose, sodium starch glycolate and stearic acid.
In addition, the 20 mg tablet contains D&C Yellow #10, FD&C Blue #1, and FD&C Yellow #6; the 30 mg tablet contains FD&C Blue #1.
This is the structural formula

Quoted from the official label, section “Description”.

Ingredients people check for

Lactose, gluten, dyes, sugars and other ingredients that matter with an allergy, intolerance or diet — as this product’s FDA label lists them.

Lactoselactose anhydrousMilk sugar: matters with lactose intolerance or a milk allergy.

Quoted from the FDA label. A label that does not name an ingredient is not a guarantee that the product is free of it, and formulations change. With an allergy, check the pack and ask a pharmacist.

Every version of this medicine (11)

The same active substance, strength and kind of form, from every company that sells it — with what each label lists.

Showing 11 of 11

Same active substance, strength and form in other countries

Matched on active substance, strength and kind of form only. This is not a statement that the products are equivalent or interchangeable: other ingredients, release and approved uses can differ — ask a pharmacist before swapping.

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Canada1 matching products

ISDN 5 mg · tablet

Every strength and form (5)

Details

Made by	AvPAK
Active substance	Isosorbide Dinitrate
Used in	Heart, blood pressure and circulation
Strength	5 mg
Form	Tablet
Route	Oral
Packs	50 BLISTER PACK in 1 BOX, UNIT-DOSE / 1 TABLET in 1 BLISTER PACK
NDC	50268-447

Source: NDC Directory · 2026-09-13 · not reviewed by a clinician

Source: US Food and Drug Administration, NDC Directory. Reuse terms: US government work (FDA).

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Other strengths and forms

52 products are sold under this name. Grouped by form; a number on a strength means several companies make it.

Tablet52 products
- 5 mg10
  5 mg · 10 companies
  +2 more
- 10 mg15
  10 mg · 15 companies
  +7 more
- 20 mg14
  20 mg · 14 companies
  +6 more
- 30 mg7
  30 mg · 7 companies
- 40 mg6
  40 mg · 6 companies

Same active substance

These contain the same substance. That does not mean one can replace another — ask a pharmacist.

Isosorbide5 mgPrescription onlyTablet BluePoint Laboratories · Isosorbide Dinitrate Isosorbide10 mgPrescription onlyTablet BluePoint Laboratories · Isosorbide Dinitrate Isosorbide20 mgPrescription onlyTablet BluePoint Laboratories · Isosorbide Dinitrate Isosorbide Dinitrate5 mgPrescription onlyTablet Hikma Pharmaceuticals USA Inc. · Isosorbide Dinitrate Isosorbide Dinitrate10 mgPrescription onlyTablet Hikma Pharmaceuticals USA Inc. · Isosorbide Dinitrate Isosorbide Dinitrate20 mgPrescription onlyTablet Hikma Pharmaceuticals USA Inc. · Isosorbide Dinitrate

See every product with Isosorbide Dinitrate