Lopressor 50mg Tablets
It is used to treat high blood pressure.It is used to treat some types of chest pain (angina).It is used after a heart attack to help prevent future heart attacks and lengthen life. It may be given to you for other reasons. Talk with the doctor.
Drug Class
Antihypertensive, Antianginal, Antiarrhythmic
Pharmacologic Class
Beta-1 Selective Adrenergic Blocker
Pregnancy Category
Category C
FDA Approved
Jun 1978
DEA Schedule
Not Controlled
Overview
What is this medicine?
Metoprolol is a type of medicine called a beta-blocker. It works by relaxing blood vessels and slowing your heart rate, which helps to lower high blood pressure, relieve chest pain (angina), and improve outcomes after a heart attack.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with or immediately after a meal. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Protect the medication from heat sources.
Missing a Dose
If you miss a dose, skip it and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with or immediately after a meal. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Protect the medication from heat sources.
Missing a Dose
If you miss a dose, skip it and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for the missed one.
Lifestyle & Tips
- Take medication exactly as prescribed, do not stop abruptly.
- Monitor blood pressure and heart rate regularly at home if advised.
- Maintain a healthy diet (low sodium, low fat).
- Engage in regular, moderate exercise as advised by your doctor.
- Limit alcohol intake.
- Avoid smoking.
- Report any new or worsening symptoms to your doctor immediately.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
Hypertension: 100 mg daily in single or divided doses. Angina: 100 mg daily in 2 divided doses. Myocardial Infarction: 100 mg twice daily.
Dose Range:
50 - 450 mg
Condition-Specific Dosing:
hypertension:
Initial: 50-100 mg/day in single or divided doses. Maintenance: 100-450 mg/day.
anginaPectoris:
Initial: 50 mg twice daily. Maintenance: 100-400 mg/day in 2 divided doses.
myocardialInfarction:
Acute: 5 mg IV every 2 minutes for 3 doses, then 50 mg orally every 6 hours for 48 hours. Maintenance: 100 mg twice daily.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Hypertension (off-label): 1-5 mg/kg/day divided twice daily, max 200 mg/day. Not routinely recommended.
Adolescent:
Hypertension (off-label): 1-5 mg/kg/day divided twice daily, max 200 mg/day. Not routinely recommended.
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed
Moderate:
No adjustment needed
Severe:
No adjustment needed
Dialysis:
Not significantly removed by hemodialysis; no supplemental dose needed.
Hepatic Impairment:
Mild:
Consider lower initial dose and careful titration.
Moderate:
Reduce dose significantly (e.g., by 50%).
Severe:
Reduce dose significantly (e.g., by 75%) and monitor closely due to extensive hepatic metabolism.
Pharmacology
Mechanism of Action
Metoprolol is a cardioselective beta-1 adrenergic receptor blocker. It selectively blocks beta-1 receptors, primarily located in the heart, reducing heart rate, myocardial contractility, and cardiac output. At higher doses, it can also block beta-2 receptors. It reduces renin release from the kidneys.
Pharmacokinetics
Absorption:
Bioavailability:
40-50% (due to significant first-pass metabolism)
Tmax:
1.5-2 hours
FoodEffect:
Food increases bioavailability by 20-40%.
Distribution:
Vd:
5.6 L/kg
ProteinBinding:
10-12%
CnssPenetration:
Limited
Elimination:
HalfLife:
3-7 hours
Clearance:
Not available (highly variable due to first-pass)
ExcretionRoute:
Renal (primarily as metabolites)
Unchanged:
<5%
Pharmacodynamics
OnsetOfAction:
Within 1 hour (oral)
PeakEffect:
2-4 hours (oral)
DurationOfAction:
10-20 hours (dose-dependent)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
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 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
Signs of low blood sugar, including:
+ Dizziness
+ Headache
+ Feeling sleepy
+ Feeling weak
+ Shaking
+ Fast heartbeat
+ Confusion
+ Hunger
+ Sweating
Depression
Severe dizziness or fainting
New or worsening chest pain
New or worsening abnormal heartbeat
Slow heartbeat
Shortness of breath, significant weight gain, or swelling in the arms or legs
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 is essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Feeling dizzy, tired, or weak
Diarrhea
Upset stomach
Vomiting
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult 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 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
Signs of low blood sugar, including:
+ Dizziness
+ Headache
+ Feeling sleepy
+ Feeling weak
+ Shaking
+ Fast heartbeat
+ Confusion
+ Hunger
+ Sweating
Depression
Severe dizziness or fainting
New or worsening chest pain
New or worsening abnormal heartbeat
Slow heartbeat
Shortness of breath, significant weight gain, or swelling in the arms or legs
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 is essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Feeling dizzy, tired, or weak
Diarrhea
Upset stomach
Vomiting
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, consult 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 dizziness or fainting
- Very slow heart rate (e.g., less than 50 beats per minute)
- Difficulty breathing or wheezing
- Swelling in ankles or feet, sudden weight gain
- Chest pain or discomfort that worsens or does not go away
- Symptoms of depression
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.
Certain heart-related conditions, including:
+ Abnormal heart rhythms, such as heart block or sick-sinus syndrome
+ Heart failure (a weakened heart)
+ Low blood pressure
+ Poor blood circulation to your arms or legs
+ Shock caused by heart problems
+ A slow heartbeat
* Respiratory conditions, such as:
+ Asthma
+ Chronic obstructive pulmonary disease (COPD) or other breathing problems
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. They will help determine if it is safe for you to take this medication with your existing health conditions and medications. Never start, stop, or adjust the dosage of any medication without consulting your doctor first.
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.
Certain heart-related conditions, including:
+ Abnormal heart rhythms, such as heart block or sick-sinus syndrome
+ Heart failure (a weakened heart)
+ Low blood pressure
+ Poor blood circulation to your arms or legs
+ Shock caused by heart problems
+ A slow heartbeat
* Respiratory conditions, such as:
+ Asthma
+ Chronic obstructive pulmonary disease (COPD) or other breathing problems
This list is not exhaustive, and it is crucial to discuss all your medications (prescription, over-the-counter, natural products, and vitamins) and health problems with your doctor and pharmacist. They will help determine if it is safe for you to take this medication with your existing health conditions and medications. Never start, stop, or adjust the dosage of any medication without consulting your doctor first.
Precautions & Cautions
Important Warnings and Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
To ensure your safety, avoid driving and performing tasks that require alertness until you understand how this medication affects you. When changing positions, rise slowly from sitting or lying down to minimize the risk of dizziness or fainting. Be cautious when climbing stairs.
Regularly monitor your blood pressure and heart rate as instructed by your doctor. Additionally, have your blood work and other laboratory tests checked as directed by your doctor. Be aware that this medication may interfere with certain lab tests, so inform all your healthcare providers and laboratory personnel that you are taking this medication.
This medication may mask symptoms of low blood sugar, such as a rapid heartbeat, which can increase the risk of severe or prolonged low blood sugar. This is particularly concerning for individuals with diabetes, children, and those who are fasting, undergoing surgery, or experiencing nausea and vomiting. If you have questions or concerns, discuss them with your doctor.
If you have diabetes, it is crucial to closely monitor your blood sugar levels. If you have high blood pressure and are taking this medication, consult your doctor before using over-the-counter products that may increase blood pressure, such as cough and cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
Do not abruptly stop taking this medication, as this may lead to worsened chest pain or even a heart attack, particularly if you have certain types of heart disease. To avoid adverse effects, your doctor will guide you on how to gradually discontinue the medication. If you experience new or worsening chest pain or other heart problems, seek medical attention immediately.
This medication may make it more challenging to recognize symptoms of an overactive thyroid, such as a rapid heartbeat. If you have an overactive thyroid and suddenly stop taking this medication, your condition may worsen and become life-threatening. Consult your doctor for guidance.
If you have a history of severe allergic reactions, inform your doctor, as you may be at risk of an even more severe reaction if you are exposed to the allergen again. If you use epinephrine to treat severe allergic reactions, discuss this with your doctor, as the medication may not be as effective while taking this medication. Also, consult your doctor before consuming alcohol.
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor to ensure the best possible outcome for you and your baby.
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
To ensure your safety, avoid driving and performing tasks that require alertness until you understand how this medication affects you. When changing positions, rise slowly from sitting or lying down to minimize the risk of dizziness or fainting. Be cautious when climbing stairs.
Regularly monitor your blood pressure and heart rate as instructed by your doctor. Additionally, have your blood work and other laboratory tests checked as directed by your doctor. Be aware that this medication may interfere with certain lab tests, so inform all your healthcare providers and laboratory personnel that you are taking this medication.
This medication may mask symptoms of low blood sugar, such as a rapid heartbeat, which can increase the risk of severe or prolonged low blood sugar. This is particularly concerning for individuals with diabetes, children, and those who are fasting, undergoing surgery, or experiencing nausea and vomiting. If you have questions or concerns, discuss them with your doctor.
If you have diabetes, it is crucial to closely monitor your blood sugar levels. If you have high blood pressure and are taking this medication, consult your doctor before using over-the-counter products that may increase blood pressure, such as cough and cold medications, diet pills, stimulants, non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen, and certain natural products or aids.
Do not abruptly stop taking this medication, as this may lead to worsened chest pain or even a heart attack, particularly if you have certain types of heart disease. To avoid adverse effects, your doctor will guide you on how to gradually discontinue the medication. If you experience new or worsening chest pain or other heart problems, seek medical attention immediately.
This medication may make it more challenging to recognize symptoms of an overactive thyroid, such as a rapid heartbeat. If you have an overactive thyroid and suddenly stop taking this medication, your condition may worsen and become life-threatening. Consult your doctor for guidance.
If you have a history of severe allergic reactions, inform your doctor, as you may be at risk of an even more severe reaction if you are exposed to the allergen again. If you use epinephrine to treat severe allergic reactions, discuss this with your doctor, as the medication may not be as effective while taking this medication. Also, consult your doctor before consuming alcohol.
If you are pregnant, plan to become pregnant, or are breastfeeding, discuss the benefits and risks of this medication with your doctor to ensure the best possible outcome for you and your baby.
Overdose Information
Overdose Symptoms:
- Severe bradycardia (very slow heart rate)
- Hypotension (low blood pressure)
- Cardiogenic shock
- Bronchospasm (difficulty breathing)
- Heart failure
- Hypoglycemia
- Cardiac arrest
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment may involve IV fluids, atropine, glucagon, vasopressors, or a pacemaker.
Drug Interactions
Contraindicated Interactions
- Fingolimod (risk of severe bradycardia)
Major Interactions
- CYP2D6 inhibitors (e.g., fluoxetine, paroxetine, quinidine, propafenone, ritonavir, bupropion, terbinafine, cimetidine, hydralazine, alcohol) - may increase metoprolol levels and effects.
- Calcium channel blockers (non-dihydropyridine like verapamil, diltiazem) - increased risk of bradycardia, AV block, and hypotension.
- Clonidine - risk of rebound hypertension upon clonidine withdrawal if beta-blocker is not tapered first.
- Digitalis glycosides - increased risk of bradycardia and AV block.
- Other antihypertensives - additive hypotensive effects.
Moderate Interactions
- NSAIDs (e.g., ibuprofen, naproxen) - may reduce antihypertensive effect of metoprolol.
- Insulin and oral hypoglycemics - beta-blockers may mask symptoms of hypoglycemia (e.g., tachycardia) and prolong hypoglycemic episodes.
- Sympathomimetics (e.g., epinephrine, norepinephrine) - may cause paradoxical hypertension and bradycardia.
- Reserpine, guanethidine - additive hypotensive and bradycardic effects.
Minor Interactions
- Alcohol - may increase metoprolol levels.
Monitoring
Baseline Monitoring
Blood Pressure (BP)
Rationale: To establish baseline and guide initial dosing.
Timing: Prior to initiation
Heart Rate (HR)
Rationale: To establish baseline and assess risk of bradycardia.
Timing: Prior to initiation
Electrocardiogram (ECG)
Rationale: To assess for pre-existing conduction abnormalities.
Timing: Prior to initiation (especially in patients with cardiac history)
Renal Function (BUN, Creatinine)
Rationale: To assess kidney function, though metoprolol is primarily hepatically metabolized, renal function is important for overall patient assessment.
Timing: Prior to initiation
Liver Function Tests (ALT, AST, Bilirubin)
Rationale: To assess hepatic function, as metoprolol is extensively metabolized by the liver.
Timing: Prior to initiation
Routine Monitoring
Blood Pressure (BP)
Frequency: Regularly (e.g., weekly initially, then monthly or quarterly once stable)
Target: <130/80 mmHg (or individualized target)
Action Threshold: Systolic >140 mmHg or Diastolic >90 mmHg (consider dose adjustment); Systolic <90 mmHg or symptomatic hypotension (consider dose reduction/discontinuation).
Heart Rate (HR)
Frequency: Regularly (e.g., weekly initially, then monthly or quarterly once stable)
Target: 50-70 bpm (resting)
Action Threshold: <50 bpm or symptomatic bradycardia (consider dose reduction/discontinuation).
Symptoms of Heart Failure Exacerbation
Frequency: Ongoing patient education and inquiry at visits
Target: N/A
Action Threshold: New or worsening shortness of breath, edema, weight gain (evaluate and manage).
Symptom Monitoring
- Bradycardia (slow heart rate)
- Hypotension (dizziness, lightheadedness, fainting)
- Fatigue, lethargy
- Shortness of breath, wheezing (especially in patients with asthma/COPD)
- Cold hands/feet
- Insomnia, nightmares
- Depression
- Masked symptoms of hypoglycemia (in diabetics)
Special Patient Groups
Pregnancy
Category C. Use during pregnancy only if the potential benefit justifies the potential risk to the fetus. Beta-blockers can cause fetal bradycardia, hypoglycemia, and growth restriction. Neonates of mothers treated with metoprolol close to delivery should be monitored for signs of beta-blockade.
Trimester-Specific Risks:
First Trimester:
Limited data, but generally avoided unless clearly necessary.
Second Trimester:
Potential for fetal growth restriction and bradycardia.
Third Trimester:
Increased risk of neonatal bradycardia, hypoglycemia, and respiratory depression at birth. Monitor neonate for 24-48 hours post-delivery.
Lactation
L2 (Moderately Safe). Metoprolol is excreted into breast milk in small amounts. While generally considered safe, monitor breastfed infants for signs of beta-blockade (e.g., bradycardia, lethargy, poor feeding).
Infant Risk:
Low risk of adverse effects in healthy, full-term infants. Higher risk in premature or medically fragile infants.
Pediatric Use
Safety and efficacy not well-established for routine pediatric use. Off-label use for hypertension or certain arrhythmias may occur under specialist supervision, with careful dose titration and monitoring.
Geriatric Use
Start with lower doses and titrate slowly due to potential for increased sensitivity to effects (e.g., bradycardia, hypotension) and potential for reduced renal/hepatic function. Monitor closely for adverse effects.
Clinical Information
Clinical Pearls
- Do NOT discontinue metoprolol abruptly, especially in patients with coronary artery disease, as it can precipitate angina, myocardial infarction, or arrhythmias. Taper dose gradually over 1-2 weeks.
- Metoprolol is cardioselective at lower doses, but loses selectivity at higher doses, potentially affecting beta-2 receptors (e.g., in lungs). Use with caution in patients with asthma, COPD, or other bronchospastic diseases.
- Can mask symptoms of hypoglycemia (e.g., tachycardia, tremors) in diabetic patients. Advise patients to monitor blood glucose closely.
- May exacerbate symptoms of peripheral vascular disease (e.g., Raynaud's phenomenon).
- Take with food or immediately after a meal to enhance absorption and reduce GI upset.
- Patients should be advised to report any signs of heart failure exacerbation (e.g., shortness of breath, swelling, weight gain).
Alternative Therapies
- Other beta-blockers (e.g., atenolol, bisoprolol, carvedilol, labetalol, propranolol)
- ACE inhibitors (e.g., lisinopril, enalapril)
- Angiotensin Receptor Blockers (ARBs) (e.g., losartan, valsartan)
- Calcium Channel Blockers (e.g., amlodipine, nifedipine, diltiazem, verapamil)
- Diuretics (e.g., hydrochlorothiazide, furosemide)
- Alpha-blockers (e.g., prazosin, doxazosin)
Cost & Coverage
Average Cost:
$10 - $50 per 30 tablets (generic 50mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 (Generic) or Tier 2 (Brand)
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 your 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 happened.