What are the recommended dosing regimens for metoprolol (tartrate and succinate) for hypertension, chronic stable angina, heart failure with reduced ejection fraction, and post‑myocardial infarction, including adjustments for hepatic or renal impairment?

Metoprolol Dosing Guidelines

Formulation Selection: Critical Clinical Decision

Metoprolol succinate (extended-release) is the only formulation proven to reduce mortality in heart failure with reduced ejection fraction and should be prescribed exclusively for this indication. 1

• Metoprolol succinate demonstrated a 34% reduction in all-cause mortality, 38% reduction in cardiovascular mortality, 41% reduction in sudden death, and 49% reduction in death from progressive heart failure in patients with HFrEF 1
• Metoprolol tartrate (immediate-release) has not been shown to reduce mortality in heart failure and should not be substituted for succinate in this population 2, 1
• For hypertension without heart failure, either formulation is acceptable, though succinate offers once-daily convenience 1

Condition-Specific Dosing Protocols

Heart Failure with Reduced Ejection Fraction (HFrEF)

Starting dose: Metoprolol succinate 12.5–25 mg once daily 1, 3

Titration schedule:

• Double the dose every 2 weeks if the preceding dose is well tolerated 1
• Target dose: 200 mg once daily 1, 3
• Minimum effective dose: 100 mg daily (50% of target) if full target dose not tolerated 1

Absolute contraindications before initiation:

• Signs of decompensated heart failure, low output state, or pulmonary congestion 1, 3
• Systolic blood pressure <100 mmHg with symptoms 1, 3
• Heart rate <60 bpm 1, 3
• Second- or third-degree AV block without functioning pacemaker 1, 3
• PR interval >0.24 seconds 3
• Active asthma or severe reactive airway disease 1, 3

Hypertension

Metoprolol tartrate:

• Starting dose: 25–50 mg twice daily 3
• Titration: Increase every 1–2 weeks based on blood pressure response 1
• Maximum dose: 200 mg twice daily 3

Metoprolol succinate:

• Starting dose: 50 mg once daily 1, 3
• Titration: Increase every 1–2 weeks 1
• Maximum dose: 400 mg once daily 1, 3

Post-Myocardial Infarction

Acute phase (IV to oral transition):

• IV: 5 mg slow bolus over 1–2 minutes, repeat every 5 minutes × 3 doses (maximum 15 mg total) 3, 4
• Begin oral metoprolol tartrate 15 minutes after last IV dose 3, 4
• Initial oral: 50 mg every 6 hours for 48 hours (or 25 mg every 6 hours if partial IV intolerance) 3, 4

Maintenance (secondary prevention):

• Transition to metoprolol succinate 200 mg once daily, titrated gradually over 2–3 weeks 1

Contraindications to IV metoprolol in acute MI:

• Systolic BP <120 mmHg 3
• Heart rate >110 bpm or <60 bpm 3
• Signs of heart failure or cardiogenic shock risk 3
• Age >70 years with multiple risk factors 3
• Killip class II–III 3

Atrial Fibrillation Rate Control

Metoprolol tartrate: 25–100 mg twice daily (maximum 200 mg twice daily) 1, 3

Metoprolol succinate: 50–400 mg once daily 1, 3

Target heart rate:

• Lenient control: <110 bpm at rest 1
• Strict control: 50–80 bpm at rest 1

IV for acute rate control:

• 5 mg IV bolus over 1–2 minutes, repeat every 5 minutes as needed (maximum 15 mg total) 3
• Transition to oral 15 minutes after last IV dose 3

Chronic Stable Angina

Metoprolol tartrate: 25–50 mg twice daily initially, titrate to 100–200 mg daily in divided doses 3

Metoprolol succinate: 50–200 mg once daily 1

Intravenous Metoprolol: Critical Safety Protocol

Standard IV dosing: 2.5–5 mg slow IV bolus over 1–2 minutes, repeat every 5 minutes based on hemodynamic response, absolute maximum 15 mg total 3, 4

This maximum applies regardless of:

• Prior oral dose 3
• Body weight 3
• Clinical indication 3

Required monitoring during IV administration:

• Continuous blood pressure and heart rate after each bolus 3
• Auscultation for new rales (pulmonary congestion) 3
• Auscultation for bronchospasm 3
• Continuous ECG monitoring 3

Critical contraindications to IV metoprolol:

• Any signs of heart failure, low output, or decompensated state 3
• Systolic BP <100–120 mmHg 3
• Heart rate <60 bpm or >110 bpm 3
• PR interval >0.24 seconds or any second/third-degree AV block 3
• Active asthma or reactive airway disease 3
• Cardiogenic shock or high risk factors (age >70, Killip class >1) 3

Evidence-based caution: The COMMIT trial demonstrated that early IV metoprolol increases cardiogenic shock by 11 per 1,000 patients, particularly in the first 24 hours 3

Dose Adjustments for Special Populations

Hepatic Impairment

• Start at lowest recommended dose with cautious gradual titration 4
• Elimination half-life may be prolonged up to 7.2 hours (normal 3–4 hours) 4
• Metoprolol blood levels increase substantially due to reduced first-pass metabolism 4

Renal Impairment

• No dose adjustment required 4
• Systemic availability and half-life do not differ clinically from normal subjects 4

Geriatric Patients

• Use low initial starting dose due to decreased hepatic function and increased drug exposure 4
• Plasma concentrations may be slightly higher but not clinically significant for most patients 4

Women

• Women achieve 50–80% higher metoprolol exposure than men at equivalent doses 1
• Consider 50% dose reduction in women with heart failure to reduce adverse effects while maintaining efficacy 1

Managing Adverse Effects During Titration

Worsening Congestion

• First: Double the diuretic dose 1
• Second: Halve the metoprolol dose only if increasing diuretic fails 1

Symptomatic Hypotension

• First: Reduce or eliminate vasodilators 1
• Second: Reduce diuretic if no congestion present 1
• Third: Temporarily reduce metoprolol dose by 50% 1

Symptomatic Bradycardia (HR <50–60 bpm with symptoms)

• Absolute contraindication to continued therapy 1
• Hold metoprolol immediately 1
• Assess for hypoperfusion, altered mental status, chest discomfort 1
• Administer atropine 0.5 mg IV every 3–5 minutes (maximum 3 mg) if severe 1
• Consider transcutaneous pacing if atropine fails 1

Critical warning: Abrupt discontinuation of metoprolol can cause severe exacerbation of angina, myocardial infarction, ventricular arrhythmias, and 2.7-fold increased 1-year mortality 1

Monitoring Parameters

During titration:

• Heart rate and blood pressure at each visit 1
• Signs of congestion (rales, edema, weight gain) 1
• Symptoms of worsening heart failure 1
• Blood chemistry at 12 weeks after initiation and 12 weeks after final dose 1

Target resting heart rate: 50–60 bpm unless limiting side effects occur 3

Common Pitfalls to Avoid

• Never substitute metoprolol tartrate for succinate in heart failure—only succinate has proven mortality benefit 2, 1
• Never give the full 15 mg IV dose as a single rapid bolus—increases hypotension and bradycardia risk 3
• Never use IV metoprolol in decompensated heart failure—increases cardiogenic shock risk 3
• Never abruptly discontinue metoprolol—taper by 25–50% every 1–2 weeks to prevent rebound 1
• Never rely on resting heart rate alone for atrial fibrillation rate control—assess during activity 1