Metoprolol
Metoprolol is a selective beta-blocker used to treat high blood pressure, chest pain, heart failure, and to prevent heart attacks. It works by slowing heart rate and reducing the heart's workload.
About Metoprolol
Metoprolol is a cardioselective beta-1 adrenergic receptor blocker also sold under brand names including Lopressor and Toprol-XL. It is primarily used to is prescribed to treat: • High blood pressure (hypertension) • Chest pain (angina) • Heart failure • Abnormal heart rhythms (atrial fibrillation, SVT) • Prevention of migraine headaches • Post heart attack (improves survival) • Hyperthyroidism symptoms It helps reduce strain on the heart and prevents cardiovascular events. Metoprolol is available in immediate-release oral tablet — lopressor (25 mg, 50 mg, 100 mg), extended-release oral tablet — toprol-xl (25 mg, 50 mg, 100 mg, 200 mg), and iv injection (1 mg/ml ampule, typically 5 mg per dose) form. Healthcare providers commonly prescribe Metoprolol for conditions including Asthma, Atrial Fibrillation, Attention Deficit Hyperactivity Disorder (ADHD), and Chronic Obstructive Pulmonary Disease (COPD).
Metoprolol at a Glance
- Brand names
- Lopressor, Toprol-XL
- Drug class
- Cardioselective Beta-1 Adrenergic Receptor Blocker
- Pregnancy category
- FDA Category Category C — Beta-blockers cross the placenta and can cause fetal bradycardia, hypoglycemia, and growth restriction. However, metoprolol is among the more commonly used beta-blockers in pregnancy when clearly indicated (e.g., maternal arrhythmia, hypertension), with risk-benefit weighed individually.
- Available forms
- Immediate-release oral tablet — Lopressor (25 mg, 50 mg, 100 mg), Extended-release oral tablet — Toprol-XL (25 mg, 50 mg, 100 mg, 200 mg), IV injection (1 mg/mL ampule, typically 5 mg per dose)
- Therapeutic categories
- Cardiovascular, Beta-Blockers, Hypertension, Heart Failure
- Conditions treated
- 15 related conditions on this site
What Metoprolol Is Used For
is prescribed to treat:
• High blood pressure (hypertension) • Chest pain (angina) • Heart failure • Abnormal heart rhythms (atrial fibrillation, SVT) • Prevention of migraine headaches • Post-heart attack (improves survival) • Hyperthyroidism symptoms
It helps reduce strain on the heart and prevents cardiovascular events.
Dosage Quick Reference
These are general dosage guidelines for Metoprolol. Your doctor will determine the appropriate dose for your specific situation.
| Condition | Starting Dose | Maintenance Dose |
|---|---|---|
| Hypertension (immediate-release) | 50 mg twice daily | 100–450 mg/day in 1–2 divided doses |
| Hypertension (extended-release) | 25–100 mg once daily | 50–400 mg once daily |
| Angina pectoris | 50 mg twice daily (IR) or 100 mg once daily (ER) | Titrate weekly to symptom control; usual 100–400 mg/day |
| Heart failure (extended-release only, NYHA II–III) | 12.5–25 mg once daily | Double dose every 2 weeks as tolerated to target 200 mg once daily |
| Acute myocardial infarction | 5 mg IV every 2 minutes x 3 doses, then 50 mg PO every 6 hours | Transition to 100 mg twice daily long-term |
| Atrial fibrillation rate control | 25–50 mg every 6–12 hours (IR) | Titrate to resting HR < 110 bpm; usual 100–400 mg/day |
Side Effects
Common side effects may include:
• Fatigue or tiredness • Dizziness or lightheadedness • Slow heart rate (bradycardia) • Cold hands and feet • Shortness of breath with exertion • Diarrhea or stomach upset • Depression or mood changes
Serious side effects (seek immediate medical attention):
• Very slow heart rate (less than 50 bpm at rest) • Severe dizziness or fainting • New or worsening shortness of breath • Swelling of ankles or feet • Unusual weight gain • Chest pain • Wheezing or difficulty breathing • Severe allergic reactions
See also: Drug Interactions ↓
Drug Interactions
Metoprolol is metabolized predominantly by CYP2D6 and has interactions tied to enzyme inhibition, additive cardiovascular effects, and competing receptor pharmacology.
- Strong CYP2D6 inhibitors (e.g., fluoxetine, paroxetine, bupropion, quinidine): Significantly raise metoprolol levels and risk of bradycardia, hypotension, and fatigue. Use lowest effective metoprolol dose and monitor closely.
- Non-dihydropyridine calcium channel blockers (e.g., verapamil, diltiazem): Additive negative inotropy and AV nodal blockade can cause severe bradycardia, heart block, or heart failure exacerbation. Combination is sometimes used but requires close monitoring; IV combination is generally avoided.
- Clonidine: Abrupt withdrawal of clonidine while on a beta-blocker can precipitate severe rebound hypertension. If discontinuing both, taper the beta-blocker first over several days, then taper clonidine.
- Digoxin: Additive bradycardia and AV block. Monitor heart rate and consider lower digoxin dose, especially in older adults.
- Insulin and oral hypoglycemics: Beta-blockers can mask the adrenergic warning signs of hypoglycemia (tachycardia, tremor) — sweating remains. Diabetic patients should be counseled to monitor glucose more closely, especially during dose changes.
- NSAIDs: May reduce the antihypertensive effect of metoprolol. Use the lowest effective NSAID dose.
See also: Questions to Ask Your Doctor ↓
Key Considerations
Known drug interactions
Metoprolol has documented interactions with other medications, supplements, and certain foods. Review the Drug Interactions section below and tell your healthcare provider about every medication you take, including over-the-counter products. Jump to section →
Multiple forms available
Metoprolol comes in more than one form (Immediate-release oral tablet — Lopressor (25 mg, 50 mg, 100 mg), Extended-release oral tablet — Toprol-XL (25 mg, 50 mg, 100 mg, 200 mg), IV injection (1 mg/mL ampule, typically 5 mg per dose)). The right form for you depends on your condition, ease of use, and your provider's recommendation.
Additional Information
What is ?
Metoprolol is one of the most commonly prescribed beta-blocker medications in the United States. It belongs to the class of selective beta-1 blockers (cardioselective), meaning it primarily affects the heart rather than other organs. Metoprolol is available in two formulations: immediate-release (Lopressor) and extended-release (Toprol-XL).
How Does Metoprolol Work?
Metoprolol works by blocking beta-1 receptors, which are primarily located in the heart:
Cardiac Effects:
- Blocks effects of adrenaline (epinephrine) on the heart
- Slows heart rate (negative chronotropic effect)
- Reduces force of heart contractions (negative inotropic effect)
- Decreases cardiac output
- Lowers blood pressure
- Reduces myocardial oxygen demand
- Prevents harmful cardiac remodeling
At Lower Doses:
- Primarily blocks beta-1 receptors (in the heart)
- "Cardioselective" - fewer effects on lungs, blood vessels
At Higher Doses:
- May also affect beta-2 receptors
- Can affect lungs, blood vessels, and metabolism
Common Uses
Cardiovascular Conditions
- Effective blood pressure control
- Reduces cardiovascular events
- Often combined with other antihypertensives
Angina (Chest Pain):
- Reduces frequency and severity of angina attacks
- Improves exercise tolerance
- Decreases need for nitroglycerin
- First-line therapy for chronic stable angina
Post-Myocardial Infarction:
- Improves survival after heart attack
- Reduces risk of recurrent MI
- Prevents sudden cardiac death
- Should be started in hospital and continued long-term
- Improves survival (reduces mortality by 35%)
- Decreases hospitalizations
- Improves symptoms over time
- Used specifically in heart failure with reduced ejection fraction (HFrEF)
- Must be started at very low doses and increased gradually
Atrial Fibrillation/Flutter:
- Controls ventricular rate
- Reduces symptoms (palpitations, shortness of breath)
- Often first-line for rate control
Supraventricular Tachycardia (SVT):
- Helps prevent episodes
- Slows heart rate during episodes
Other Uses
Migraine Prevention:
- Reduces frequency of migraine headaches
- Usually requires several weeks to see benefit
- Typical dose: 50-200 mg daily
Hyperthyroidism:
- Controls symptoms (rapid heart rate, tremor, anxiety)
- Used while treating underlying thyroid condition
Dosage and Administration
Metoprolol comes in two formulations:
Immediate-Release (Metoprolol Tartrate/Lopressor):
- Usually taken 2-3 times daily
- For hypertension: 25-100 mg twice daily
- For angina: 50-100 mg twice daily
- For heart failure: Start 12.5-25 mg twice daily, increase gradually
Extended-Release (Metoprolol Succinate/Toprol-XL):
- Taken once daily
- For hypertension: 25-200 mg once daily
- For heart failure: Start 12.5-25 mg once daily, increase gradually to target 200 mg daily
- Preferred formulation for heart failure
Administration Tips:
- Take at the same time(s) each day
- Can be taken with or without food, but be consistent
- Extended-release: Swallow whole, don't crush or chew
- Immediate-release can be split if scored
- For heart failure: Start very low and increase slowly (every 2 weeks)
- Take with meals to reduce dizziness
Important Safety Information
Who Should Not Take Metoprolol?
Avoid metoprolol if you have:
- Severe bradycardia (very slow heart rate)
- Heart block (second or third degree without pacemaker)
- Sick sinus syndrome (without pacemaker)
- Severe peripheral arterial disease
- Decompensated heart failure (acute, requiring IV medications)
- Cardiogenic shock
- Severe asthma or COPD (relative contraindication)
Drug Interactions
Important interactions include:
Cardiac Medications:
- Calcium channel blockers (diltiazem, verapamil) - may cause severe bradycardia or heart block
- Digoxin - additive effects on heart rate
- Other beta-blockers - avoid concurrent use
- Antiarrhythmics (amiodarone, dronedarone) - increased bradycardia risk
Medications Affecting Metoprolol Levels:
- CYP2D6 inhibitors (fluoxetine, paroxetine, bupropion, quinidine) - increase metoprolol levels
- Rifampin - decreases metoprolol levels
Other Interactions:
- Insulin/diabetes medications - may mask hypoglycemia symptoms
- Clonidine - don't stop both simultaneously (risk of rebound hypertension)
- NSAIDs - may reduce blood pressure-lowering effects
- Epinephrine - may cause severe hypertension or bradycardia
NEVER Stop Suddenly
⚠️ CRITICAL WARNING: Never stop metoprolol abruptly without medical supervision. Sudden discontinuation can cause:
- Rebound hypertension (severe blood pressure increase)
- Worsening angina
- Heart attack
- Life-threatening arrhythmias
- Sudden cardiac death
If discontinuation is necessary, taper gradually over 1-2 weeks under medical supervision.
Pregnancy and Breastfeeding
Pregnancy:
- Category C - use only if benefit outweighs risk
- May be used for severe hypertension in pregnancy
- Can cause fetal bradycardia and low blood sugar in newborn
- Discuss alternatives with doctor
Breastfeeding:
- Small amounts enter breast milk
- Generally considered compatible
- Monitor infant for signs of beta-blockade (slow heart rate, low blood sugar)
Monitoring and Follow-Up
Regular monitoring includes:
Heart Rate:
- Check regularly, both at rest and with activity
- Target resting rate: 55-70 bpm (varies by indication)
- Report consistently <50 bpm or >100 bpm
- Home monitoring encouraged
Blood Pressure:
- Regular home monitoring
- Check sitting and standing pressures initially
- Target varies by individual
Heart Failure Patients:
- Weight daily (report 2-3 lb gain in a day or 5 lb in a week)
- Monitor for worsening symptoms initially
- Symptoms may temporarily worsen when starting but improve long-term
Blood Sugar (Diabetics):
- Monitor more frequently when starting
- Metoprolol may mask hypoglycemia symptoms
- Sweating with hypoglycemia is NOT masked
Periodic Testing:
- ECG if heart rhythm concerns
- Echocardiogram in heart failure (monitor ejection fraction improvement)
Managing Side Effects
Fatigue
Very common, especially when starting or increasing dose:
- Often improves after 2-4 weeks
- Take largest dose at bedtime if possible
- Maintain regular sleep schedule
- Exercise as tolerated (improves energy over time)
- Discuss dose adjustment if persistent
Dizziness/Lightheadedness
Common, especially with position changes:
- Rise slowly from sitting or lying
- Stay well hydrated
- Avoid alcohol
- Take with food
- Usually improves with time
- Report severe or persistent dizziness
Cold Hands and Feet
Due to reduced peripheral blood flow:
- Wear warm socks and gloves
- Layer clothing
- Avoid extreme cold
- Exercise improves circulation
- Usually tolerable and improves
Shortness of Breath
Can occur, especially with exertion:
- Expected initially in heart failure patients
- Often improves after 2-3 months in heart failure
- Report worsening shortness of breath
- If asthma/COPD worsens, may need medication change
Sexual Side Effects
Can occur in men:
- Erectile dysfunction possible
- Decreased libido
- Discuss with doctor - dose adjustment or alternative medications available
Special Populations
Diabetic Patients:
- May mask symptoms of hypoglycemia (rapid heart rate, tremor)
- Sweating with low blood sugar NOT masked
- Monitor blood glucose more frequently
- Still important medication for diabetics with heart disease
- Benefits usually outweigh risks
Asthma/COPD:
- Use with extreme caution
- May worsen bronchospasm
- Cardioselective at low doses (less lung effect)
- Often better tolerated than non-selective beta-blockers
- Monitor lung function closely
Peripheral Vascular Disease:
- May worsen symptoms (claudication)
- Monitor for worsening leg pain
- Benefits for heart disease often outweigh risks
Elderly:
- Start with lower doses
- More prone to dizziness and falls
- Monitor heart rate carefully
- Otherwise well-tolerated
Thyroid Disease:
- May mask symptoms of hyperthyroidism
- Don't stop abruptly in hyperthyroid patients
- Monitor thyroid function
Heart Failure Specific Information
Starting Metoprolol in Heart Failure
Critical Points:
- Must be STABLE (not acutely decompensated)
- Start at VERY LOW dose (12.5-25 mg daily)
- Increase SLOWLY (double dose every 2 weeks)
- Symptoms may WORSEN initially (first 2-4 weeks)
- IMPROVES outcomes significantly if patient tolerates titration
- Target dose: 200 mg daily (metoprolol succinate)
Expected Course:
- First 2-4 weeks: May feel worse (more tired, short of breath)
- 2-3 months: Symptoms begin improving
- 6-12 months: Significant improvement in symptoms and exercise tolerance
- Long-term: Improved survival, fewer hospitalizations
Requires Patience:
- Patient education crucial
- Close follow-up essential
- Don't give up during initial worsening period
- Benefits are substantial for those who can tolerate
Lifestyle Considerations
While taking metoprolol:
- Exercise regularly (may need to adjust intensity - heart rate won't increase as much)
- Monitor heart rate during exercise
- Use perceived exertion rather than target heart rate for exercise intensity
- Maintain heart-healthy diet
- Limit alcohol (enhances blood pressure-lowering effects)
- Avoid extreme cold exposure
- Stay hydrated
- Don't skip doses
- Carry medical information card
- Inform all providers you take metoprolol
When to Contact Your Doctor
Seek immediate medical attention if you experience:
- Very slow heart rate (<50 bpm at rest with symptoms)
- Severe dizziness or fainting
- Chest pain
- Severe shortness of breath
- Sudden weight gain (heart failure patients)
- Swelling of ankles/feet (new or worsening)
- Wheezing or trouble breathing
- Signs of low blood sugar (diabetics)
Contact your doctor for routine issues:
- Persistent fatigue affecting daily activities
- Sexual side effects
- Depression or mood changes
- Questions about exercise or target heart rate
- Planning surgery or dental procedures
- New medications from other doctors
- Worsening asthma or COPD symptoms
Clinical Benefits
Extensive evidence shows metoprolol:
For Hypertension:
- Effectively lowers blood pressure
- Reduces stroke and heart attack risk
For Heart Failure:
- Reduces mortality by 34%
- Decreases hospitalizations by 30%
- Improves exercise tolerance and quality of life
- Improves heart function (ejection fraction)
Post-Heart Attack:
- Reduces mortality by 25-40%
- Prevents recurrent heart attack
- Reduces sudden cardiac death
- One of the most important post-MI medications
For Angina:
- Reduces angina frequency by 50-70%
- Improves exercise capacity
- Decreases nitroglycerin use
Formulation Differences
Immediate-Release (Metoprolol Tartrate):
- Shorter acting - taken 2-3 times daily
- Less expensive
- Used for acute situations
- Works well for blood pressure, angina, rate control
Extended-Release (Metoprolol Succinate):
- Once-daily dosing
- Smoother blood levels
- PREFERRED for heart failure (only formulation proven to reduce mortality)
- Better adherence due to once-daily dosing
- More expensive but usually covered by insurance
Not Interchangeable:
- 100 mg tartrate is NOT equivalent to 100 mg succinate
- Formulations have different indications
- Always verify which formulation prescribed
Storage
Store metoprolol at room temperature (68-77°F/20-25°C) away from light, heat, and moisture. Keep in original container. Keep out of reach of children.
Cost and Availability
Both formulations available as affordable generics. Metoprolol tartrate is very inexpensive and on $4 generic lists. Metoprolol succinate (extended-release) costs more but still affordable as generic. Both covered by virtually all insurance plans.
Disclaimer: This information is for educational purposes only and is not intended to replace professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified healthcare provider with any questions about a medical condition or medication.
Frequently Asked Questions
Questions to Ask Your Doctor About Metoprolol
Consider discussing these topics at your next appointment:
- How will we know whether metoprolol is doing its job?
- What heart rate or blood pressure readings should make me call you?
- Are any of my other medications interacting with metoprolol?
- Should I be checking my blood pressure and pulse at home?
- If side effects bother me, what alternatives are reasonable?
Medical Disclaimer: This information is for educational purposes only and should not be considered medical advice. Always consult with your healthcare provider before starting, stopping, or changing any medication. Your doctor can provide personalized recommendations based on your specific health condition and medical history.