Isosorbide Mononitrate 20 mg Tablet, 100-count
🆔 Identity & classification
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🏭 Manufacturer & labeler
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🩺 Clinical
- Isosorbide is designed to prevent chest pain (angina) from starting in the first place, not to stop an attack that's already happening. It works by relaxing and widening your blood...
- What exactly does this medication do — will it stop my chest pain when it happens?
- Yes, headaches are very common when you first start isosorbide — they happen because the medication widens blood vessels, including in your head. The good news is that headaches us...
- I keep getting headaches since starting this — is that normal, and will it go away?
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 776XM7047L
Calcium stearate is a white powder derived from stearic acid and calcium. It works as a lubricant and glidant to help the medicine flow smoothly during manufacturing and prevent ingredients from sticking to equipment.
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UNII J9EQA3S2JM
FD&C Blue No. 1 Aluminum Lake is a blue colorant made by combining FD&C Blue No. 1 dye with aluminum salts. It is used to color tablets, capsules, and other medicines for easy identification and appearance.
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UNII EWQ57Q8I5X
Lactose monohydrate is a natural sugar derived from milk. It serves as a filler and binder in tablets and capsules, helping create the proper size, texture, and consistency of the medicine.
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UNII OP1R32D61U
Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
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UNII ETJ7Z6XBU4
Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.
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UNII O8232NY3SJ
A plant-based carbohydrate derived from corn kernels. It acts as a filler to add bulk, a binder to hold ingredients together, and a disintegrant to help the tablet break apart in your stomach for absorption.
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UNII 7SEV7J4R1U
A powder made from a naturally occurring mineral. In medicines, talc works as a glidant and anti-caking agent, helping tablets and capsules flow smoothly during manufacturing and preventing clumping.
7 inactive ingredients listed in the exact product block matched to this NDC.
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ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
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💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per ea | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | $2.383 | $238.29 / 100 tablets |
| Medicaid paysCMS SDUD · 12 mo | $0.5485 | $54.85 / 100 tablets |
| Medicare drug plans payPart D · Q2 2026 | $1.01 | $100.95 / 100 tablets |
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🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| isosorbide mononitrate 20 mg 62175-0107-01 | Lannett | 100 tablets | $0.152 | AB | FDA listed | save 94% |
| Isosorbide Mononitrate 20 mgthis 00228-2620-11 | Actavis | 100 tablets | $2.383 | — | Availability likely | — |
| Isosorbide Mononitrate 20 mg 62559-0253-01 | ANI | 100 tablets | $2.383 | AB | Availability likely | — |
| isosorbide mononitrate 20 mg 81665-0103-10 | OMNIVIUM | 100 tablets | $2.383 | AB | Availability likely | — |
| isosorbide mononitrate 20 mg 63187-0900-30 | Proficient | 30 tablets | — | AB | FDA listed | — |
| Isosorbide Mononitrate 20 mg 64950-0251-01 | Genus | 100 tablets | — | AB | FDA listed | — |
| isosorbide mononitrate 20 mg 67046-1578-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
FDA-approved generic versions are listed, and recent pricing/market data suggests they may be available — see Therapeutic equivalents.
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🗺️ Medicaid utilization & spend
💊 Medicaid utilization by pack size
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
🔬 Reported adverse events (FAERS)
Top reported reactions
Reporter sex
Serious outcomes
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📦 Packaging — all sizes for this product
| Package NDC | Description | Per unit | Per pack | Marketing start | Status |
|---|---|---|---|---|---|
| 00228-2620-11 You're viewing this | 100 TABLET in 1 BOTTLE (0228-2620-11) | $2.38 / ea | $238.29 | 1998-10-30 | Active |
| 00228-2620-00 | 41667 TABLET in 1 CONTAINER (0228-2620-00) | — | — | — | Active |
You're viewing the smallest of 2 pack sizes for this product.
In Medicaid, this is the most-dispensed pack of this product — about 100% of fills over the last four reported quarters. See all packs ↓
Pack size FAQ
What quantity is in NDC 00228-2620-11?
What is the difference between NDC 00228-2620-11 and NDC 00228-2620-00?
What NDC number is used to bill for this package of Isosorbide Mononitrate 20 mg Tablet?
Prices are the latest CMS NADAC pharmacy acquisition cost per NDC; per-pack figures are per-unit × pack quantity, shown only when the pack is denominated in the same measure NADAC prices.
🧭 About this NDC listing & data coverage
What "drug for further processing" means
FDA lists this package under the "drug for further processing" marketing category: Actavis Pharma, Inc. supplies it to other companies for further processing or repackaging (blister cards that are later repackaged or co-packaged are a common example). The units themselves are a finished dosage form — which is why pricing or Medicaid data can still appear — but this exact package code may not be the presentation a retail pharmacy dispenses.
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| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | ✓ Available |
| Orange Book / therapeutic-equivalence data | — Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope. |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | ✓ Available |
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📄 Full FDA label FDA SPL
🎯 Indications and Usage ▾
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.
⏱️ Dosage and Administration ▾
DOSAGE AND ADMINISTRATION The recommended regimen of isosorbide mononitrate tablets is 20 mg twice daily, with the doses seven hours apart. A starting dose of 5 mg (½ tablet of the 10 mg dosing strength) might be appropriate for persons of particularly small stature but should be increased to at least 10 mg by the second or third day of therapy. Dosage adjustments are not necessary for elderly patients or patients with altered hepatic or renal function.
As noted above ( CLINICAL PHARMACOLOGY ), multiple studies of organic nitrates have shown that maintenance of continuous 24-hour plasma levels results in refractory tolerance. The asymmetric (2 doses, 7 hours apart) dosing regimen for isosorbide mononitrate tablets provides a daily nitrate-free interval to minimize the development of tolerance. As also noted under CLINICAL PHARMACOLOGY , well-controlled studies have shown that tolerance to isosorbide mononitrate tablets occurs to some extent when using the twice-daily regimen in which the two doses are given seven hours apart.
This regimen has been shown to have antianginal efficacy beginning one hour after the first dose and lasting at least seven hours after the second dose. The duration (if any) of antianginal activity beyond fourteen hours has not been studied. In clinical trials, isosorbide mononitrate has been administered in a variety of regimens and doses.
Doses above 20 mg twice-a-day (with the doses seven hours apart) have not been adequately studied. Doses of 5 mg twice-a-day are clearly effective (effectiveness based on exercise tolerance) for only the first day of a twice-a-day (with doses 7 hours apart) regimen.
⛔ Contraindications ▾
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.
🤒 Adverse Reactions ▾
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. Extremely rarely, ordinary doses of organic nitrates have caused methemoglobinemia in normal-seeming patients; for further discussion of its diagnosis and treatment see under OVERDOSAGE . To report SUSPECTED ADVERSE REACTIONS, contact Teva at 1-888-838-2872 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
🔄 Drug Interactions ▾
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.
🤰 Pregnancy ▾
Pregnancy Teratogenic Effects Reproduction studies performed in rats and rabbits at doses of up to 540 and 810 mg/kg/day, respectively, have revealed no evidence of harm to the fetus due to isosorbide mononitrate. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, isosorbide mononitrate should be used during pregnancy only if clearly needed.
Nonteratogenic Effects Birth weights, neonatal survival and development, and incidence of stillbirths were adversely affected when pregnant rats were administered oral doses of 540 (but not 270) mg isosorbide mononitrate/kg/day during late gestation and lactation. This dose was associated with decreased maternal body weight gain and decreased maternal motor activity. Daily Dose (mg/kg) Multiple of MRHD* Based on: Species Body Weight Body Surface Rabbit 810 1013 375 Rat 900 1125 195 540 675 117 500 625 108 360 450 78 270 338 59 Calculations assume a human weight of 50 kg and human body surface area of 1.46 m 2 , a rabbit weight of 2 kg and rabbit body surface area of 0.163 m 2 , and a rat weight of 150 g and rat body surface area of 0.025 m 2 . *Maximum recommended human dose (MRHD) is 20 mg bid (twice-a-day)
🧒 Pediatric Use ▾
Pediatric Use Safety and effectiveness of isosorbide mononitrate in pediatric patients have not been established.
🧓 Geriatric Use ▾
Geriatric Use Clinical studies of isosorbide mononitrate 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.
🆘 Overdosage ▾
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.
In patients with renal disease or congestive heart failure, therapy resulting in central volume expansion is not without hazard. Treatment of isosorbide mononitrate overdose in these patients may be subtle and difficult, and invasive monitoring may be required. Methemoglobinemia Methemoglobinemia has been reported in patients receiving other organic nitrates, and it probably could also occur as a side effect of isosorbide mononitrate.
Certainly nitrate ions liberated during metabolism of isosorbide mononitrate can oxidize hemoglobin into methemoglobin. Even in patients totally without cytochrome b 5 reductase activity, however, and even assuming that the nitrate moiety of isosorbide mononitrate is quantitatively applied to oxidation of hemoglobin, about 2 mg/kg of isosorbide mononitrate should be required before any of these patients manifests clinically significant (greater than or equal to 10%) methemoglobinemia. In patients with normal reductase function, significant production of methemoglobin should require even larger doses of isosorbide mononitrate.
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 7.8 to 11.1 mg of isosorbide mononitrate 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 arte…
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Isosorbide mononitrate is the major active metabolite of isosorbide dinitrate (ISDN), and most of the clinical activity of the dinitrate is attributable to the mononitrate. The principal pharmacological action of isosorbide mononitrate is relaxation of vascular smooth muscle and consequent dilatation of peripheral arteries and veins, especially the latter. Dilation 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).
Arteriolar relaxation reduces systemic vascular resistance, systolic arterial pressure, and mean arterial pressure (afterload). Dilation of the coronary arteries also occurs. The relative importance of preload reduction, afterload reduction and coronary dilatation remains undefined.
Pharmacodynamics Dosing regimens for most chronically used drugs are designed to provide plasma concentrations that are continuously greater than a minimally effective concentration. This strategy is inappropriate for organic nitrates. Several well-controlled clinical trials have used exercise testing to assess the antianginal efficacy of continuously-delivered nitrates.
In the large majority of these trials, active agents were indistinguishable from placebo after 24 hours (or less) of continuous therapy. Attempts to overcome tolerance by dose escalation, even to doses far in excess of those used acutely, have consistently failed. Only after nitrates have been absent from the body for several hours has their antianginal efficacy been restored.
The drug-free interval sufficient to avoid tolerance to isosorbide mononitrate has not been completely defined. In the only regimen of twice-daily isosorbide mononitrate that has been shown to avoid development of tolerance, the two doses of isosorbide mononitrate tablets are given 7 hours apart, so there is a gap of 17 hours between the second dose of each day and the first dose of the next day. Taking account of the relatively long half-life of isosorbide mononitrate this result is consistent with those obtained for other organic nitrates.
The asymmetric twice-daily regimen of isosorbide mononitrate tablets successfully avoided significant rebound/withdrawal effects. The incidence and magnitude of such phenomena have appeared, in studies of other nitrates, to be highly dependent upon the schedule of nitrate administration. Pharmacokinetics Isosorbide mononitrate is rapidly and completely absorbed from the gastrointestinal tract.
In humans, isosorbide mononitrate is not subject to first pass metabolism in the liver. The absolute bioavailability of isosorbide mononitrate from isosorbide mononitrate tablets is nearly 100%. Peak plasma concentrations usually occur in about 30 to 60 minutes.
Isosorbide mononitrate exhibits dose proportionality over the recommended dose range. Food does not significantly affect the absorption or bioavailability of isosorbide mononitrate. Metoprolol coadministration did not change the pharmacokinetics of isosorbide mononitrate.
The volume of distribution is approximately
0.6L/kg. Plasma protein binding of isosorbide mononitrate was found to be less than 5%. When radiolabelled isosorbide mononitrate was administered to humans in order to elucidate the metabolic fate, about half of the dose was found denitrated and renally excreted as isosorbide and sorbitol.
One quarter of the dose was accounted for as conjugates of the parent drug in the urine. None of these metabolites is vasoactive. Only 2% of the dose was excreted as unchanged drug.
The overall elimination half-life of isosorbide mononitrate is about 5 hours. The rate of clearance is the same in healthy young adults, in patients with various degrees of renal, hepatic or cardiac dysfunction and in the elderly. When radiolabelled isosorbide mononitrate was administered to humans, 93% of the dose was excreted within 48 hours into the urine.
Renal excre…
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED Isosorbide mononitrate tablets, USP are available as follows: 10 mg — Each blue, round, tablet imprinted with and 631 on one side and scored on the other side, contains 10 mg of isosorbide mononitrate (diluted), USP. Tablets are supplied in bottles of 100 (NDC 0228-2631-11). 20 mg — Each blue, round, tablet imprinted with and 620 on one side and scored on the other side, contains 20 mg of isosorbide mononitrate (diluted), USP.
Tablets are supplied in bottles of 100 (NDC 0228-2620-11). Dispense in tight containers as defined in the USP. Store at 25ºC (77ºF); excursions permitted to 15º to 30ºC (59º to 86ºF).
Keep tightly closed. Manufactured In Bulgaria By: Balkanpharma - Dupnitsa AD Dupnitsa 2600, Bulgaria Manufactured For: Teva Pharmaceuticals Parsippany, NJ 07054 Rev. A 10/2022 596e94e8-figure-02 596e94e8-figure-03
📋 Description ▾
DESCRIPTION Isosorbide mononitrate (diluted), USP, an organic nitrate, is a vasodilator with effects on both arteries and veins. The molecular 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, contain 10 mg or 20 mg of isosorbide mononitrate (diluted), USP.
In addition, each tablet contains the following inactive ingredients: calcium stearate, colloidal silicon dioxide, corn starch, FD&C Blue #1 HT Aluminum Lake, lactose monohydrate, microcrystalline cellulose, and talc. 596e94e8-figure-01
💬 Information for Patients ▾
Information for Patients Patients should be told that the antianginal efficacy of isosorbide mononitrate tablets can be maintained by carefully following the prescribed schedule of dosing (two doses taken seven hours apart). For most patients, this can be accomplished by taking the first dose on awakening and the second dose 7 hours later. As with other nitrates, daily headaches sometimes accompany treatment with isosorbide mononitrate.
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 mononitrate, since loss of headache may be associated with simultaneous loss of antianginal efficacy. Aspirin and/or acetaminophen, on the other hand, often successfully relieve isosorbide mononitrate-induced headaches with no deleterious effect on isosorbide mononitrate’s antianginal efficacy.
Treatment with isosorbide mononitrate may be associated with light-headedness 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.