Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
Quick facts
- Drug class
- Nitrate Vasodilator [EPC]
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 311192
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
INDICATIONS AND USAGE Isosorbide Mononitrate Tablets USP are indicated for the prevention and treatment of angina pectoris due to coronary artery disease. The onset of action of oral isosorbide mononitrate is not sufficiently rapid for this product to be useful in aborting an acute anginal episode.
About this medicine
DESCRIPTION Isosorbide mononitrate, an organic nitrate, is a vasodilator with effects on both arteries and veins. The empirical formula is C 6 H 9 NO 6 and the molecular weight is 191.14. The chemical name for Isosorbide mononitrate is 1,4:3,6-Dianhydro-D-glucitol 5-nitrate and the compound has the following structural formula: Isosorbide Mononitrate Tablets USP, for oral administration, are available in 10 mg and 20 mg tablets. Each tablet contains the following inactive ingredients: lactose monohydrate, microcrystalline cellulose, sodium starch glycolate, povidone, magnesium stearate, polyvinyl alcohol, polyethylene glycol, titanium dioxide, and talc. The 20 mg tablets also contain D&C yellow #10 aluminum lake, FD&C yellow #6 aluminum lake, and FD&C blue #2 aluminum lake. FDA approved dissolution test specifications differ from USP. Stucture
Who should not take it
CONTRAINDICATIONS Isosorbide mononitrate is contraindicated in patients who are allergic to it. Do not use isosorbide mononitrate 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 mononitrate in patients who are taking the soluble guanylate cyclase stimulator riociguat. Concomitant use can cause hypotension.
Warnings
WARNINGS Amplification of the vasodilatory effects of isosorbide mononitrate 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 isosorbide mononitrate in patients with acute myocardial infarction or congestive heart failure have not been established. Because the effects of isosorbide mononitrate are difficult to terminate rapidly, this drug is not recommended in these settings. If isosorbide mononitrate is used in these conditions, careful clinical or hemodynamic monitoring must be used to avoid the hazards of hypotension and tachycardia.
Reported side effects
ADVERSE REACTIONS Headache is the most frequent side effect and was the cause of 2% of all dropouts from controlled-clinical trials. Headache decreased in incidence after the first few days of therapy. The following table shows the frequency of adverse reactions observed in 1% or more of subjects in 6 placebo-controlled trials, conducted in the United States and abroad. The same table shows the frequency of withdrawal for these adverse reactions. In many cases the adverse reactions were of uncertain relation to drug treatment. Frequency Of Adverse Reactions (Discontinuations)* 6 Placebo-Controlled Studies Dose Placebo 5 mg 10 mg 20 mg Patients 160 54 52 159 Headache 6% (0%) 17% (0%) 13% (0%) 35% (5%) Fatigue 2% (0%) 0% (0%) 4% (0%) 1% (0%) Upper Respiratory Infection <1% (0%) 0% (0%) 4% (0%) 1% (0%) Pain <1% (0%) 4% (0%) 0% (0%) <1% (0%) Dizziness 1% (0%) 0% (0%) 0% (0%) 4% (0%) Nausea <1% (0%) 0% (0%) 0% (0%) 3% (2%) Increased Cough <1% (0%) 0% (0%) 2% (0%) <1% (0%) Rash 0% (0%) 2% (2%) 0% (0%) <1% (0%) Abdominal Pain <1% (0%) 0% (0%) 2% (0%) 0% (0%) Allergic Reaction 0% (0%) 0% (0%) 2% (0%) 0% (0%) Cardiovascular Disorder 0% (0%) 2% (0%) 0% (0%) 0% (0%) Chest Pain <1% (0%) 0% (0%) 2% (0%) <1% (0%) Diarrhea 0% (0%) 0% (0%) 2% (0%) 0% (0%) Flushing 0% (0%) 0% (0%) 2% (0%) 0% (0%) Emotional Lability 0% (0%) 2% (0%) 0% (0%) 0% (0%) Pruritus 1% (0%) 2% (2%) 0% (0%) 0% (0%) *Some individuals discontinued for multiple reasons. Other adverse reactions, each reported by fewer than 1% of exposed patients, and in many cases of uncertain relation to drug treatment, were: Cardiovascular: acute myocardial infarction, apoplexy, arrhythmias, bradycardia, edema, hypertension, hypotension, pallor, palpitations, tachycardia. Dermatologic: sweating. Gastrointestinal: anorexia, dry mouth, dyspepsia, thirst, vomiting, decreased weight. Genitourinary: prostatic disorder. Miscellaneous: amblyopia, back pain, bitter taste, muscle cramps, neck pain, paresthesia, susurrus aurium. Neurologic: anxiety, impaired concentration, depression, insomnia, nervousness, nightmares, restlessness, tremor, vertigo. Respiratory: asthma, dyspnea, sinusitis. […]
Interactions with other medicines
Drug Interactions Concomitant use of isosorbide mononitrate with phosphodiesterase inhibitors in any form is contraindicated (see CONTRAINDICATIONS ). Concomitant use of isosorbide mononitrate with riociguat, a soluble guanylate cyclase stimulator, is contraindicated (see CONTRAINDICATIONS ). The vasodilating effects of isosorbide mononitrate may be additive with those of other vasodilators. Alcohol, in particular, has been found to exhibit additive effects of this variety. Marked symptomatic orthostatic hypotension has been reported when calcium channel blockers and organic nitrates were used in combination. Dose adjustments of either class of agents may be necessary.
If too much is taken
OVERDOSAGE Hemodynamic Effects The ill effects of isosorbide mononitrate overdose are generally the results of isosorbide mononitrate’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 mononitrate and its metabolites are not widely available, and such determinations have, in any event, no established role in the management of isosorbide mononitrate overdose. There are no data suggesting what dose of isosorbide mononitrate is likely to be life-threatening in humans. In rats and mice, there is significant lethality at oral doses of 1965 mg/kg and 2581 mg/kg, respectively. No data are available to suggest physiological maneuvers (e.g., maneuvers to change the pH of the urine) that might accelerate elimination of isosorbide mononitrate. Isosorbide mononitrate is significantly removed from the blood during hemodialysis. No specific antagonist to the vasodilator effects of isosorbide mononitrate is known, and no intervention has been subject to controlled study as a therapy of isosorbide mononitrate overdose. Because the hypotension associated with isosorbide mononitrate overdose is the result of venodilatation and arterial hypovolemia, prudent therapy in this situation should be directed toward an 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. […]
Before you take anything new
Tell your pharmacist or doctor about every medicine you take — including ones bought without a prescription, herbal products and supplements. Interactions are one of the most common avoidable causes of harm from medicines, and a pharmacist can check your full list in a couple of minutes.
This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 27 March 2026. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.