Isosorbide Dinitrate 5mg Oral Tabs
It is used to prevent chest pain (angina pectoris) in people with heart disease.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antianginal
Pharmacologic Class
Organic Nitrate; Vasodilator
Pregnancy Category
Category C
FDA Approved
Jan 1951
DEA Schedule
Not Controlled
Overview
What is this medicine?
Isosorbide dinitrate is a medication that helps relax and widen your blood vessels. This makes it easier for blood to flow to your heart, reducing chest pain (angina). It's used to prevent angina attacks or to treat them when they happen.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, take it exactly as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. If you need to stop taking this medication, do not stop suddenly without first consulting your doctor, as this may increase your risk of side effects. Instead, your doctor will advise you on how to gradually taper off the medication.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, away from direct light and moisture. Keep the container in a dry place, such as a closet or cupboard, and avoid storing it in a bathroom. Make sure to keep the lid tightly closed. It is also essential to keep all medications out of the reach of children and pets to prevent accidental ingestion.
What to Do If You Miss a Dose
If you forget to take a dose, take it as soon as you remember. However, if it is almost time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
To get the most benefit from your medication, take it exactly as directed by your doctor. Carefully read all the information provided with your prescription, and follow the instructions closely. If you need to stop taking this medication, do not stop suddenly without first consulting your doctor, as this may increase your risk of side effects. Instead, your doctor will advise you on how to gradually taper off the medication.
Storing and Disposing of Your Medication
To maintain the effectiveness and safety of your medication, store it at room temperature, away from direct light and moisture. Keep the container in a dry place, such as a closet or cupboard, and avoid storing it in a bathroom. Make sure to keep the lid tightly closed. It is also essential to keep all medications out of the reach of children and pets to prevent accidental ingestion.
What to Do If You Miss a Dose
If you forget to take a dose, take it as soon as you remember. However, if it is almost time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
Lifestyle & Tips
- Avoid sudden changes in position (e.g., standing up quickly) to prevent dizziness or fainting.
- Avoid alcohol consumption, as it can increase the risk of dizziness and low blood pressure.
- Maintain a nitrate-free interval (typically 10-14 hours daily) for oral forms to prevent tolerance (the medication becoming less effective).
- Do not stop taking the medication suddenly without consulting your doctor, as this can worsen angina.
- Carry sublingual tablets with you at all times if prescribed for acute angina.
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:
Oral: 5 to 30 mg, 2 to 3 times daily (for prophylaxis); Sublingual: 2.5 to 10 mg for acute angina
Dose Range:
5 - 30 mg
Condition-Specific Dosing:
angina_prophylaxis:
5 to 30 mg orally, 2 to 3 times daily (with a nitrate-free interval of 14 hours daily to prevent tolerance)
acute_angina:
2.5 to 10 mg sublingually, repeated every 5 to 10 minutes as needed, up to 3 doses in 15-30 minutes
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No specific dose adjustment recommended, use with caution
Moderate:
No specific dose adjustment recommended, use with caution
Severe:
No specific dose adjustment recommended, use with caution due to potential for accumulation of active metabolites
Dialysis:
Not significantly dialyzable; use with caution, monitor for hypotension
Hepatic Impairment:
Mild:
No specific dose adjustment recommended, use with caution
Moderate:
No specific dose adjustment recommended, use with caution due to extensive hepatic metabolism
Severe:
No specific dose adjustment recommended, use with caution due to extensive hepatic metabolism
Pharmacology
Mechanism of Action
Isosorbide dinitrate is an organic nitrate that is metabolized to nitric oxide (NO) in vascular smooth muscle. NO activates guanylate cyclase, increasing intracellular cyclic guanosine monophosphate (cGMP), which leads to dephosphorylation of myosin light chains and relaxation of smooth muscle. This results in venodilation (decreasing preload) and arterial dilation (decreasing afterload), reducing myocardial oxygen demand and improving blood flow to ischemic areas of the myocardium.
Pharmacokinetics
Absorption:
Bioavailability:
Oral: 20-25% (due to extensive first-pass metabolism); Sublingual: High (avoids first-pass)
Tmax:
Oral: 1 hour; Sublingual: 6 minutes
FoodEffect:
Food may delay absorption but does not significantly affect the extent of absorption.
Distribution:
Vd:
Not available (highly variable)
ProteinBinding:
Not available
CnssPenetration:
Limited
Elimination:
HalfLife:
Isosorbide dinitrate: 1 hour; Isosorbide-5-mononitrate: 5 hours; Isosorbide-2-mononitrate: 2 hours
Clearance:
Not available
ExcretionRoute:
Renal (primarily as glucuronide conjugates of metabolites)
Unchanged:
<1%
Pharmacodynamics
OnsetOfAction:
Oral: 20-60 minutes; Sublingual: 2-5 minutes
PeakEffect:
Oral: 45-120 minutes; Sublingual: 15-30 minutes
DurationOfAction:
Oral: 4-6 hours; Sublingual: 1-3 hours
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Attention Immediately
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical help right away:
- 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, or swelling of the mouth, face, lips, tongue, or throat
- Severe dizziness or fainting
- Abnormal heart rhythms, including fast or slow heartbeat
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people do not experience any side effects or only have mild 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 do not go away, contact your doctor for advice:
- Headaches, especially when starting the medication. In most cases, headaches improve over time. Do not adjust your medication use without consulting your doctor, as they can provide guidance on managing this side effect.
Reporting Side Effects
This list does not include all possible side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical help right away:
- 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, or swelling of the mouth, face, lips, tongue, or throat
- Severe dizziness or fainting
- Abnormal heart rhythms, including fast or slow heartbeat
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although many people do not experience any side effects or only have mild 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 do not go away, contact your doctor for advice:
- Headaches, especially when starting the medication. In most cases, headaches improve over time. Do not adjust your medication use without consulting your doctor, as they can provide guidance on managing this side effect.
Reporting Side Effects
This list does not include all possible side effects. If you have questions or concerns about side effects, consult your doctor. For medical advice about side effects, contact your doctor. 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 or persistent headache (especially new onset or worsening)
- Dizziness or lightheadedness that doesn't go away
- Fainting (syncope)
- Blurred vision
- Unusual weakness or fatigue
- Chest pain that worsens or does not respond to the usual dose
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 symptoms you experienced.
Certain health conditions, including:
+ Heart failure (a weakened heart)
+ A recent heart attack
If you are currently taking any of the following medications:
+ Avanafil
+ Riociguat
+ Sildenafil
+ Tadalafil
+ Vardenafil
Please note that this is not an exhaustive list of all potential interactions. To ensure your safety, it is crucial to discuss all of your:
Prescription and over-the-counter (OTC) medications
Natural products
Vitamins
* Health problems
with your doctor and pharmacist. They will help you determine whether it is safe to take this medication in conjunction with your other medications and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting 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 symptoms you experienced.
Certain health conditions, including:
+ Heart failure (a weakened heart)
+ A recent heart attack
If you are currently taking any of the following medications:
+ Avanafil
+ Riociguat
+ Sildenafil
+ Tadalafil
+ Vardenafil
Please note that this is not an exhaustive list of all potential interactions. To ensure your safety, it is crucial to discuss all of your:
Prescription and over-the-counter (OTC) medications
Natural products
Vitamins
* Health problems
with your doctor and pharmacist. They will help you determine whether it is safe to take this medication in conjunction with your other medications and health conditions. Never start, stop, or adjust the dosage of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
If you are using this drug to manage chest pain, it is crucial to understand that it will not provide immediate relief during an attack. Instead, this medication is designed to help prevent or reduce the frequency of chest pain episodes. If you experience new or worsening chest pain or pressure, seek emergency medical attention immediately.
To ensure your safety, avoid driving and other activities that require alertness until you are familiar with how this medication affects you. To minimize the risk of dizziness or fainting, stand up slowly after sitting or lying down, and exercise caution when navigating stairs. Additionally, monitor your blood pressure and heart rate as directed by your doctor.
Before consuming alcohol, discuss the potential risks and benefits with your doctor. Long-term, uninterrupted use of this medication may lead to decreased effectiveness, a phenomenon known as tolerance. To mitigate this risk, your doctor may recommend a daily "nitrate-free" period. If you notice a decrease in the medication's efficacy, consult your doctor; do not exceed the prescribed dosage.
If you are pregnant, planning to become pregnant, or breastfeeding, it is vital to discuss the potential benefits and risks of this medication with your doctor to make an informed decision about its use.
If you are using this drug to manage chest pain, it is crucial to understand that it will not provide immediate relief during an attack. Instead, this medication is designed to help prevent or reduce the frequency of chest pain episodes. If you experience new or worsening chest pain or pressure, seek emergency medical attention immediately.
To ensure your safety, avoid driving and other activities that require alertness until you are familiar with how this medication affects you. To minimize the risk of dizziness or fainting, stand up slowly after sitting or lying down, and exercise caution when navigating stairs. Additionally, monitor your blood pressure and heart rate as directed by your doctor.
Before consuming alcohol, discuss the potential risks and benefits with your doctor. Long-term, uninterrupted use of this medication may lead to decreased effectiveness, a phenomenon known as tolerance. To mitigate this risk, your doctor may recommend a daily "nitrate-free" period. If you notice a decrease in the medication's efficacy, consult your doctor; do not exceed the prescribed dosage.
If you are pregnant, planning to become pregnant, or breastfeeding, it is vital to discuss the potential benefits and risks of this medication with your doctor to make an informed decision about its use.
Overdose Information
Overdose Symptoms:
- Severe throbbing headache
- Profound hypotension (very low blood pressure)
- Palpitations
- Flushing
- Perspiration
- Nausea
- Vomiting
- Dizziness
- Vertigo
- Tachycardia (fast heart rate)
- Methemoglobinemia (rare, but serious, causing bluish skin, lips, and nail beds, shortness of breath, fatigue)
What to Do:
Seek immediate medical attention. Call 911 or your local emergency number. For poison control, call 1-800-222-1222. Treatment is supportive, focusing on maintaining blood pressure and treating methemoglobinemia if present.
Drug Interactions
Contraindicated Interactions
- Phosphodiesterase-5 (PDE5) inhibitors (e.g., sildenafil, tadalafil, vardenafil, avanafil) - concurrent use can cause profound and prolonged hypotension, myocardial infarction, and death.
- Riociguat (soluble guanylate cyclase stimulator) - concurrent use can cause profound hypotension.
Major Interactions
- Other vasodilators (e.g., alpha-blockers, calcium channel blockers, hydralazine) - additive hypotensive effects.
- Antihypertensive agents (e.g., ACE inhibitors, ARBs, diuretics, beta-blockers) - additive hypotensive effects.
- Alcohol - enhances hypotensive effects.
Moderate Interactions
- Tricyclic antidepressants - may cause orthostatic hypotension.
- Ergotamine - nitrates may reduce the anti-migraine effect of ergotamine.
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 with changes in therapy; monitor closely after sublingual administration for acute angina.
Target: Maintain within patient's normal range, avoiding symptomatic hypotension.
Action Threshold: Symptomatic hypotension (e.g., dizziness, syncope), or systolic BP <90 mmHg.
Heart Rate (HR)
Frequency: Regularly, especially during dose titration.
Target: Maintain within patient's normal range.
Action Threshold: Significant reflex tachycardia or bradycardia.
Angina Symptoms
Frequency: Ongoing assessment by patient report.
Target: Reduction in frequency, severity, and duration of angina episodes.
Action Threshold: Increased frequency or severity of angina, or lack of response to therapy.
Headache/Dizziness
Frequency: Ongoing assessment by patient report.
Target: Tolerance often develops to headache; dizziness should be minimal.
Action Threshold: Severe or persistent headache, or recurrent dizziness/syncope.
Symptom Monitoring
- Headache (common, often resolves with continued use)
- Dizziness
- Lightheadedness
- Fainting (syncope)
- Flushing
- Nausea
- Vomiting
- Palpitations
- Blurred vision
Special Patient Groups
Pregnancy
Category C. Animal studies have shown adverse effects, but there are no adequate and well-controlled studies in pregnant women. Use only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Potential for fetal harm based on animal data; avoid if possible.
Second Trimester:
Use with caution, monitor maternal hemodynamics.
Third Trimester:
Use with caution, monitor maternal hemodynamics.
Lactation
It is not known whether isosorbide dinitrate or its metabolites are excreted in human milk. Caution should be exercised when administered to a nursing woman. Consider the benefits of breastfeeding, the risk of potential infant drug exposure, and the risk of untreated maternal condition.
Infant Risk:
L3 (Moderate risk - no human data, but molecular weight is low enough for potential transfer; monitor infant for hypotension, feeding difficulties).
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Use is generally not recommended.
Geriatric Use
Elderly patients may be more susceptible to the hypotensive effects of nitrates and may require lower initial doses and careful titration. Monitor closely for dizziness and orthostatic hypotension.
Clinical Information
Clinical Pearls
- Tolerance (tachyphylaxis) can develop with continuous use of nitrates. To prevent this, a daily nitrate-free interval (typically 10-14 hours) is recommended for oral formulations.
- Headache is a very common side effect, especially at the beginning of therapy. It often subsides with continued use as tolerance develops. Patients should be counseled that this is a sign the drug is working.
- Sublingual tablets are for acute angina attacks and should be taken at the first sign of pain. Patients should be instructed to sit down before taking to minimize dizziness.
- Patients must be educated about the absolute contraindication with PDE5 inhibitors (e.g., Viagra, Cialis) due to the risk of life-threatening hypotension.
- Isosorbide dinitrate is a prodrug, metabolized to active mononitrate metabolites (isosorbide-2-mononitrate and isosorbide-5-mononitrate), which also contribute to its therapeutic effects and duration of action.
Alternative Therapies
- Isosorbide mononitrate (for angina prophylaxis)
- Nitroglycerin (sublingual, spray, patch, ointment, IV for acute or chronic angina)
- Beta-blockers (e.g., metoprolol, atenolol) for angina prophylaxis
- Calcium channel blockers (e.g., amlodipine, diltiazem, verapamil) for angina prophylaxis
- Ranolazine (for chronic angina)
- Coronary revascularization (PCI or CABG) for appropriate patients
Cost & Coverage
Average Cost:
$10 - $50 per 30 tablets (5mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 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 taken, the amount, and the time it occurred.