What is the recommended dosing for metoprolol (metoprolol tartrate)?

Metoprolol Tartrate Dosing

For hypertension, start metoprolol tartrate at 25-50 mg twice daily and titrate to a maximum of 200 mg daily; for acute myocardial infarction, administer three 5 mg IV boluses at 2-minute intervals (15 mg total) followed by 50 mg orally every 6 hours starting 15 minutes after the last IV dose. 1, 2

Hypertension Dosing

• Initial dose: 25-50 mg orally twice daily 1
• Maximum dose: 200 mg daily (100 mg twice daily) 1
• Titration interval: Increase gradually every 1-2 weeks based on blood pressure response 1
• Target blood pressure: <130/80 mmHg for most patients 1

The American College of Cardiology emphasizes that metoprolol tartrate requires twice-daily dosing due to its shorter half-life compared to the extended-release succinate formulation 1. If once-daily dosing is preferred for adherence, consider switching to metoprolol succinate 50-200 mg once daily (maximum 400 mg daily) 1.

Acute Myocardial Infarction Dosing

IV Phase (Early Treatment)

• Administer three 5 mg IV boluses over 1-2 minutes each, separated by approximately 2-minute intervals 2
• Maximum total IV dose: 15 mg 1, 2
• Critical monitoring: Continuously monitor blood pressure, heart rate, and ECG during IV administration 2

Transition to Oral Therapy

• Begin oral therapy 15 minutes after the last IV dose 1, 2
• Initial oral dose: 50 mg every 6 hours for 48 hours in patients who tolerate the full IV dose 2
• For patients with intolerance: Start 25-50 mg every 6 hours depending on degree of intolerance 2
• Maintenance dose: 100 mg twice daily after the initial 48-hour period 2

Absolute Contraindications

Do not administer metoprolol tartrate if any of the following are present: 1

• Signs of heart failure, low output state, or increased risk for cardiogenic shock 1
• PR interval >0.24 seconds 1
• Second or third-degree heart block without a functioning pacemaker 1
• Active asthma or reactive airways disease 1
• Systolic BP <120 mmHg with risk factors for shock 1
• Sinus tachycardia >110 bpm or heart rate <60 bpm 1

Supraventricular Tachycardia/Atrial Fibrillation

• IV administration: 5 mg over 1-2 minutes, repeated every 5 minutes as needed to maximum 15 mg total 1
• Oral maintenance: 25-100 mg twice daily for rate control 1
• Target resting heart rate: 50-60 beats per minute unless limiting side effects occur 1

Special Populations

Hepatic Impairment

• Initiate at low doses with cautious gradual titration due to substantially increased blood levels 2
• Consider starting at 12.5 mg twice daily rather than standard 25-50 mg 1

Geriatric Patients (>65 years)

• Use low initial starting doses given greater frequency of decreased hepatic, renal, or cardiac function 2
• Start at 12.5-25 mg twice daily and titrate slowly 1

Renal Impairment

• No dose adjustment required 2

Critical Monitoring Parameters

• Blood pressure and heart rate at each visit during titration 1
• Signs of worsening heart failure: increased dyspnea, fatigue, edema, weight gain 1
• Bronchospasm: particularly during initiation and with IV administration 1
• Target resting heart rate: 50-60 beats per minute 1

Common Pitfalls to Avoid

• Never abruptly discontinue metoprolol tartrate as this can cause rebound hypertension, severe exacerbation of angina, myocardial infarction, and ventricular arrhythmias with 50% mortality rate in one study 1
• Do not give full 15 mg IV dose as single rapid bolus as this significantly increases hypotension and bradycardia risk 1
• Avoid IV administration in decompensated heart failure until clinical stabilization occurs 1
• Do not use in pre-excited atrial fibrillation (WPW syndrome) as it may paradoxically accelerate ventricular response 1

Important Note on Formulations

Metoprolol tartrate (immediate-release) is NOT interchangeable with metoprolol succinate (extended-release) for heart failure. Only metoprolol succinate has demonstrated mortality reduction in heart failure trials 3, 4. For heart failure with reduced ejection fraction, use metoprolol succinate 12.5-25 mg once daily titrated to target dose of 200 mg once daily 3.