What is the typical starting dose of metoprolol (beta-blocker) for a patient with hypertension or angina?

Metoprolol Dosing Guidelines

Hypertension

For hypertension, initiate metoprolol tartrate at 25-50 mg twice daily or metoprolol succinate extended-release at 50-200 mg once daily, with a maximum dose of 200 mg daily for tartrate and 400 mg daily for succinate. 1

• The typical maintenance dose range for hypertension is 50-200 mg twice daily for metoprolol tartrate (immediate-release formulation) 2
• Metoprolol succinate (extended-release) can be dosed 50-200 mg once daily for hypertension, offering the convenience of single daily dosing 1
• Beta-blockers are not recommended as first-line agents for hypertension unless the patient has coexisting ischemic heart disease or heart failure 3
• Dosage can be increased gradually every 1-2 weeks if blood pressure control is not achieved 1
• Target blood pressure reduction should be at least 20/10 mmHg, ideally to 140/90 mmHg 1

Angina Pectoris

For stable angina, the usual dose of metoprolol is 50-200 mg twice daily, with dosing adjusted to achieve a target resting heart rate of 50-60 beats per minute. 2

• The dose range studied in clinical trials for angina was 100-400 mg daily, demonstrating effective antianginal action 4
• Metoprolol should be initiated orally within the first 24 hours in patients with unstable angina/NSTEMI, in the absence of contraindications such as heart failure, hypotension, or hemodynamic instability 2
• For patients requiring more aggressive initial management, intravenous metoprolol may be given in 5-mg increments by slow IV administration (over 1-2 minutes), repeated every 5 minutes for a total initial dose of 15 mg 2
• After tolerating the full 15-mg IV dose, oral therapy can be initiated 15 minutes after the last IV dose at 25-50 mg every 6 hours for 48 hours, then transitioned to a maintenance dose of up to 100 mg twice daily 2

Acute Myocardial Infarction

In the early phase of acute MI, administer three IV boluses of 5 mg metoprolol at 2-minute intervals (total 15 mg), followed by oral metoprolol 50 mg every 6 hours starting 15 minutes after the last IV dose. 4

• After 48 hours of the every-6-hour regimen, transition to a maintenance dose of 100 mg orally twice daily 2, 4
• Patients who do not tolerate the full IV dose should start on 25-50 mg orally every 6 hours (depending on degree of intolerance) 15 minutes after the last IV dose 4
• Avoid early aggressive IV beta-blockade in hemodynamically unstable patients, as it poses substantial risk of cardiogenic shock, particularly in those with heart failure, hypotension, older age, higher heart rate, or lower blood pressure 2

Heart Failure with Reduced Ejection Fraction (HFrEF)

For heart failure, use only metoprolol succinate extended-release, starting at 12.5-25 mg once daily and titrating every 2 weeks to a target dose of 200 mg once daily. 1, 3

• Metoprolol succinate is the only metoprolol formulation proven to reduce mortality in heart failure; metoprolol tartrate lacks this evidence 3
• The titration schedule should follow: 12.5 mg → 25 mg → 50 mg → 100 mg → 200 mg once daily, doubling the dose every 2 weeks as tolerated 1, 3
• The target dose of 200 mg daily achieved a 34% reduction in all-cause mortality in the MERIT-HF trial 3
• If the full target dose cannot be achieved, aim for at least 50% of target dose (100 mg daily minimum), as some beta-blocker is better than none 1, 3
• For worsening congestion during titration, double the diuretic dose first and only halve the beta-blocker dose if increasing diuretic fails 3

Critical Contraindications and Precautions

Absolute contraindications include signs of heart failure, low output state, increased risk for cardiogenic shock, PR interval >0.24 seconds, second or third-degree heart block, and active asthma or reactive airways disease. 1

• Risk factors for cardiogenic shock include age >70 years, systolic BP <120 mmHg, heart rate >110 bpm or <60 bpm, and increased time since symptom onset 1
• Avoid IV metoprolol in patients with decompensated heart failure, hypotension, or hemodynamic instability 2, 1
• During IV beta-blocker therapy, perform frequent checks of heart rate and blood pressure, continuous ECG monitoring, and auscultation for rales and bronchospasm 2
• Never abruptly discontinue metoprolol, as this can precipitate rebound hypertension or worsening angina 1

Special Populations

• Hepatic impairment: Initiate at low doses with cautious gradual titration, as metoprolol blood levels increase substantially in hepatic dysfunction 4
• Renal impairment: No dose adjustment required 4
• Geriatric patients: Use a low initial starting dose given greater frequency of decreased organ function 4
• Poor CYP2D6 metabolizers (about 8% of Caucasians): Exhibit several-fold higher plasma concentrations, decreasing cardioselectivity 4