Isosorbide Mononitrate 120mg ER Tab
It is used to prevent chest pain (angina pectoris) in people with heart disease.Do not use this drug to treat sudden chest pain. It will not help. Talk with your doctor.
Drug Class
Antianginal agent
Pharmacologic Class
Organic nitrate
Pregnancy Category
Category B
FDA Approved
Aug 1991
DEA Schedule
Not Controlled
Overview
What is this medicine?
Isosorbide mononitrate is a medication used to prevent chest pain (angina) caused by heart disease. It works by relaxing and widening blood vessels, which helps blood flow more easily to the heart and reduces the heart's workload. This medication is not for treating sudden chest pain attacks.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. Do not stop taking this medication abruptly without consulting your doctor, as this may increase your risk of side effects. If you need to stop taking this medication, your doctor will advise you on how to taper off slowly.
Daily Dosage
If you take this medication once a day, take it in the morning when you wake up, unless your doctor directs you otherwise. Swallow the medication whole; do not chew, break, or crush it. However, some products may be broken in half; consult with your doctor to confirm.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To get the most benefit from your medication, it's essential to follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. Do not stop taking this medication abruptly without consulting your doctor, as this may increase your risk of side effects. If you need to stop taking this medication, your doctor will advise you on how to taper off slowly.
Daily Dosage
If you take this medication once a day, take it in the morning when you wake up, unless your doctor directs you otherwise. Swallow the medication whole; do not chew, break, or crush it. However, some products may be broken in half; consult with your doctor to confirm.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry place, avoiding the bathroom. Keep all medications in a safe location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Take this medication exactly as prescribed, usually once daily in the morning. Do not crush, chew, or break the extended-release tablet; swallow it whole.
- Do not stop taking this medication suddenly without consulting your doctor, as it can worsen your angina.
- Avoid or limit alcohol consumption, as it can increase the risk of dizziness and low blood pressure.
- Be cautious when standing up quickly from a sitting or lying position to avoid dizziness or fainting.
- Maintain a nitrate-free interval (typically 14 hours) as instructed by your doctor to prevent tolerance to the medication's effects.
- This medication is for prevention, not for immediate relief of angina. Always carry your fast-acting nitrate (e.g., nitroglycerin sublingual) for acute attacks.
Available Forms & Alternatives
Available Strengths:
- Isosorbide Dinitrate 30mg Oral Tabs
- Isosorbide Dinitrate 5mg Oral Tabs
- Isosorbide Dinitrate 20mg Tablets
- Isosorbide Dinitrate 10mg Oral Tabs
- Isosorbide Mononitrate 10mg Tabs
- Isosorbide Mononitrate 120mg ER Tab
- Isosorbide Mononitrate 30mg ER Tabs
- Isosorbide Mononitrate 60mg ER Tabs
- Isosorbide Mononitrate 60mg ER Tabs
- Isosorbide Dinitrate 40mg Tablets
- Isosorbide Mononitrate 30mg ER Tabs
- Isosorbide Mononitrate 120mg ER Tab
- Isosorbide Mononitrate 20mg Tabs
- Isosorbide Mononitrate 20mg Tabs
- Isosorbide Mononitrate 10mg Tabs
Dosing & Administration
Adult Dosing
Standard Dose:
30 mg or 60 mg extended-release tablet orally once daily in the morning. The 120 mg dose is a higher maintenance dose.
Dose Range:
30 - 240 mg
Condition-Specific Dosing:
anginaProphylaxis:
Initial: 30 mg or 60 mg ER orally once daily. Titrate to 120 mg ER once daily as needed. Doses up to 240 mg ER once daily have been used.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment generally required.
Moderate:
No specific dose adjustment generally required, but monitor for increased effects.
Severe:
Use with caution; consider lower starting doses and careful titration due to potential for accumulation of active metabolites. Monitor for adverse effects.
Dialysis:
Not well studied; use with caution and monitor closely. Isosorbide mononitrate is dialyzable.
Hepatic Impairment:
Mild:
No specific dose adjustment generally required.
Moderate:
No specific dose adjustment generally required.
Severe:
No specific dose adjustment generally required, as hepatic metabolism is not extensive and does not involve first-pass effect. However, use with caution in severe impairment due to potential for altered pharmacokinetics.
Pharmacology
Mechanism of Action
Isosorbide mononitrate is an organic nitrate that acts as a vasodilator. It is metabolized to nitric oxide (NO), which activates guanylate cyclase, leading to an increase in cyclic guanosine monophosphate (cGMP) in smooth muscle cells. Increased cGMP causes dephosphorylation of myosin light chains, resulting in smooth muscle relaxation and vasodilation. This primarily affects venous capacitance vessels, leading to peripheral pooling of blood, reduced venous return to the heart (preload reduction), and decreased ventricular end-diastolic volume and pressure. Arterial dilation also occurs, reducing systemic vascular resistance (afterload reduction). The overall effect is a reduction in myocardial oxygen demand, which alleviates angina.
Pharmacokinetics
Absorption:
Bioavailability:
90-100%
Tmax:
3-4 hours (for ER formulation)
FoodEffect:
Food does not significantly affect the bioavailability of isosorbide mononitrate ER, but may slightly delay Tmax.
Distribution:
Vd:
0.6 L/kg
ProteinBinding:
<5%
CnssPenetration:
Limited
Elimination:
HalfLife:
5 hours
Clearance:
Not available
ExcretionRoute:
Renal (primarily as glucuronide and denitrated metabolites)
Unchanged:
Approximately 2% (renal)
Pharmacodynamics
OnsetOfAction:
Approximately 1 hour (for ER formulation)
PeakEffect:
3-4 hours (for ER formulation)
DurationOfAction:
Up to 12-14 hours (for ER formulation, allowing for a nitrate-free interval)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Abnormal heartbeat (fast or slow)
New or worsening chest pain
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for guidance:
Dizziness
Headaches (common when starting the medication, but often improves over time; do not adjust your dosage without consulting your doctor)
* Other side effects not listed here
Reporting Side Effects
If you have questions or concerns about side effects, consult your doctor for medical advice. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Abnormal heartbeat (fast or slow)
New or worsening chest pain
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or persist, contact your doctor for guidance:
Dizziness
Headaches (common when starting the medication, but often improves over time; do not adjust your dosage without consulting your doctor)
* Other side effects not listed here
Reporting Side Effects
If you have questions or concerns about side effects, consult your doctor for medical advice. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe headache (common, but report if debilitating or persistent)
- Dizziness, lightheadedness, or fainting (especially when standing up)
- Blurred vision
- Unusual weakness or fatigue
- Fast or pounding heartbeat
- Signs of allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have a history of heart failure, also known as a weak heart.
If you have recently had a heart attack.
If you are currently taking any of the following medications: Avanafil, riociguat, sildenafil, tadalafil, or vardenafil.
Please note that this is not an exhaustive list of all potential interactions. Therefore, it is crucial to discuss all of your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. This will help ensure that it is safe to take this medication in conjunction with your other medications and health conditions.
Remember, do not start, stop, or change the dosage of any medication without first consulting your doctor to confirm that it is safe to do so.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have a history of heart failure, also known as a weak heart.
If you have recently had a heart attack.
If you are currently taking any of the following medications: Avanafil, riociguat, sildenafil, tadalafil, or vardenafil.
Please note that this is not an exhaustive list of all potential interactions. Therefore, it is crucial to discuss all of your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. This will help ensure that it is safe to take this medication in conjunction with your other medications and health conditions.
Remember, do not start, stop, or change the dosage of any medication without first consulting your doctor to confirm that it is safe to do so.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This will help ensure your safety and prevent any potential interactions with other treatments.
To minimize the risk of accidents, avoid driving and other activities that require alertness until you understand how this medication affects you. When getting up from a sitting or lying position, rise slowly to reduce the likelihood of dizziness or fainting. Be cautious when climbing stairs to avoid falls.
Regularly monitor your blood pressure as instructed by your healthcare provider. Additionally, be aware that this medication may interfere with certain laboratory tests. Inform all your healthcare providers and laboratory personnel that you are taking this medication to ensure accurate test results.
Before consuming alcohol, consult with your doctor to discuss any potential risks. If you experience new or worsening chest pain or pressure, seek emergency medical attention immediately.
Long-term use of this medication without interruption can lead to reduced effectiveness, a phenomenon known as tolerance. To avoid this, your doctor may recommend a daily "nitrate-free" period. If you notice that the medication is no longer working as well as it should, consult with your doctor. Do not exceed the prescribed dosage.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
You may notice the appearance of a tablet-like substance in your stool, but this is a normal occurrence and not a cause for concern. However, if you have any questions or concerns, discuss them with your doctor.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. You will need to discuss the potential benefits and risks of this medication to both you and your baby.
To minimize the risk of accidents, avoid driving and other activities that require alertness until you understand how this medication affects you. When getting up from a sitting or lying position, rise slowly to reduce the likelihood of dizziness or fainting. Be cautious when climbing stairs to avoid falls.
Regularly monitor your blood pressure as instructed by your healthcare provider. Additionally, be aware that this medication may interfere with certain laboratory tests. Inform all your healthcare providers and laboratory personnel that you are taking this medication to ensure accurate test results.
Before consuming alcohol, consult with your doctor to discuss any potential risks. If you experience new or worsening chest pain or pressure, seek emergency medical attention immediately.
Long-term use of this medication without interruption can lead to reduced effectiveness, a phenomenon known as tolerance. To avoid this, your doctor may recommend a daily "nitrate-free" period. If you notice that the medication is no longer working as well as it should, consult with your doctor. Do not exceed the prescribed dosage.
If you are 65 years or older, use this medication with caution, as you may be more susceptible to side effects.
You may notice the appearance of a tablet-like substance in your stool, but this is a normal occurrence and not a cause for concern. However, if you have any questions or concerns, discuss them with your doctor.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. You will need to discuss the potential benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Severe hypotension (very low blood pressure)
- Persistent throbbing headache
- Flushing
- Palpitations
- Dizziness, vertigo
- Nausea, vomiting
- Diaphoresis (sweating)
- Syncope (fainting)
- Methemoglobinemia (rare, but serious; symptoms include cyanosis, dyspnea, confusion, seizures)
What to Do:
Seek immediate medical attention or call Poison Control (1-800-222-1222). Management includes supportive care, elevation of legs, IV fluids for hypotension. Methylene blue may be used for severe methemoglobinemia.
Drug Interactions
Contraindicated Interactions
- Phosphodiesterase-5 (PDE5) inhibitors (e.g., sildenafil, tadalafil, vardenafil, avanafil) - concurrent use can cause profound and prolonged hypotension, syncope, and myocardial infarction.
- Riociguat (soluble guanylate cyclase stimulator) - concurrent use can cause profound hypotension.
Major Interactions
- Other vasodilators (e.g., alpha-blockers, calcium channel blockers, other antihypertensives) - additive hypotensive effects.
- Alcohol - may enhance hypotensive effects.
Moderate Interactions
- Tricyclic antidepressants - may reduce the hypotensive effect of nitrates.
- Phenothiazines - may reduce the hypotensive effect of nitrates.
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and assess for hypotension risk.
Timing: Prior to initiation of therapy.
Heart Rate (HR)
Rationale: To establish baseline and assess for reflex tachycardia.
Timing: Prior to initiation of therapy.
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly, especially during dose titration and if symptoms of hypotension occur.
Target: Maintain within patient's normal range, avoiding symptomatic hypotension.
Action Threshold: Systolic BP <90 mmHg or symptomatic hypotension (dizziness, syncope).
Heart Rate (HR)
Frequency: Regularly, especially during dose titration.
Target: Maintain within patient's normal range.
Action Threshold: Significant reflex tachycardia (>100 bpm or symptomatic).
Angina Symptoms
Frequency: Ongoing assessment at each visit.
Target: Reduction in frequency, severity, and duration of angina episodes.
Action Threshold: Persistent or worsening angina, indicating inadequate control.
Symptom Monitoring
- Headache (common, often transient)
- Dizziness or lightheadedness (especially upon standing)
- Flushing
- Nausea
- Hypotension (symptoms like fainting, weakness)
- Palpitations
- Blurred vision
Special Patient Groups
Pregnancy
Isosorbide mononitrate is Pregnancy Category B. Animal studies have not shown harm to the fetus, but there are no adequate and well-controlled studies in pregnant women. Use only if clearly needed.
Trimester-Specific Risks:
First Trimester:
No increased risk of congenital anomalies observed in animal studies.
Second Trimester:
No specific risks identified beyond general pregnancy considerations.
Third Trimester:
No specific risks identified beyond general pregnancy considerations.
Lactation
Isosorbide mononitrate is considered L3 (Moderately Safe) according to LactMed. It is unknown if isosorbide mononitrate is excreted in human milk. Due to its short half-life and low protein binding, infant exposure is likely low. Monitor breastfed infants for hypotension, headache, or flushing.
Infant Risk:
Low to moderate risk; monitor for adverse effects.
Pediatric Use
Safety and efficacy have not been established in pediatric patients. Not recommended for routine use.
Geriatric Use
Elderly patients may be more susceptible to the hypotensive effects of nitrates. Use with caution, starting with lower doses and titrating slowly. Monitor blood pressure closely.
Clinical Information
Clinical Pearls
- Isosorbide mononitrate ER is for prophylaxis of angina, not for acute angina attacks. Patients should have a fast-acting nitrate (e.g., sublingual nitroglycerin) for acute relief.
- A nitrate-free interval (typically 10-14 hours) is crucial to prevent the development of nitrate tolerance. The once-daily morning dosing of ER formulations helps achieve this.
- Headache is a common side effect, especially at the beginning of therapy, and often diminishes with continued use. It indicates the drug is working. Analgesics can be used for relief.
- Counsel patients on the absolute contraindication with PDE5 inhibitors (e.g., Viagra, Cialis) due to the risk of severe, life-threatening hypotension.
- Patients should be advised to swallow the extended-release tablet whole and not to crush, chew, or break it, as this can lead to rapid release of the drug and potentially dangerous effects.
Alternative Therapies
- Beta-blockers (e.g., metoprolol, atenolol)
- Calcium channel blockers (e.g., amlodipine, diltiazem, verapamil)
- Ranolazine
- Ivabradine (for chronic stable angina with normal sinus rhythm)
Cost & Coverage
Average Cost:
Varies widely, typically $10-$100+ per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication, including the amount taken and the time it happened, to facilitate prompt and effective treatment.