What is the recommended dosage and administration of metoprolol tartrate for patients with hypertension or angina?

Metoprolol Tartrate Dosing and Administration

Hypertension

For hypertension, initiate metoprolol tartrate at 50 mg twice daily and titrate to a maintenance dose of 100-200 mg twice daily (maximum 200 mg twice daily), with dose adjustments every 1-2 weeks based on blood pressure response. 1, 2, 3

• The typical starting dose is 50 mg twice daily, though 25 mg twice daily may be used in patients with concerns about tolerance 2, 3
• Maintenance dosing ranges from 50-200 mg twice daily, with most patients requiring 100-200 mg daily for adequate control 1, 3
• Beta-blockers are not first-line agents for uncomplicated hypertension unless the patient has coexisting ischemic heart disease or heart failure 1, 3
• Target blood pressure should be <130/80 mm Hg, with reductions of at least 20/10 mm Hg 1, 2

Alternative Formulation

• Metoprolol succinate (extended-release) can be dosed 50-200 mg once daily (maximum 400 mg daily) for improved adherence 2, 3, 4

Angina Pectoris

For stable angina, start metoprolol tartrate at 50 mg twice daily and titrate to 100-200 mg twice daily, targeting a resting heart rate of 50-60 beats per minute unless limiting side effects occur. 1, 2, 3

• The dose range of 50-200 mg twice daily is effective for reducing anginal attacks and improving exercise tolerance 1, 3
• Titrate based on heart rate response and symptom control, with adjustments every 1-2 weeks 2, 3
• Beta-blockers are effective first-line therapy for angina, reducing exercise-induced ischemia and preventing coronary events 1
• Higher doses (200 mg twice daily) may provide superior 24-hour antianginal coverage compared to lower doses 5, 6

Acute Coronary Syndromes (Unstable Angina/NSTEMI)

In patients with unstable angina or NSTEMI without contraindications, administer intravenous metoprolol 5 mg over 1-2 minutes, repeated every 5 minutes for a total of 15 mg, followed by oral therapy 15 minutes after the last IV dose at 25-50 mg every 6 hours for 48 hours, then transition to 100 mg twice daily. 1, 2, 3

• IV administration is warranted in patients with ongoing rest pain, especially with tachycardia or hypertension 1, 2
• After 48 hours of every-6-hour dosing, transition to maintenance dose of 100 mg twice daily 2, 3
• Do not use IV metoprolol in hemodynamically unstable patients, as this substantially increases risk of cardiogenic shock 1, 2, 3

Critical Contraindications

Absolute contraindications include signs of heart failure or low output state, increased risk for cardiogenic shock, PR interval >0.24 seconds, second- or third-degree AV block without a functioning pacemaker, active asthma or reactive airways disease, systolic BP <90 mm Hg, heart rate <50 bpm, or evidence of hypoperfusion. 1, 2, 3

Risk Factors for Cardiogenic Shock

• Age >70 years 2, 3
• Systolic BP <120 mm Hg 1, 2, 3
• Heart rate >110 bpm or <60 bpm 2, 3
• Killip Class II or III heart failure 1
• Increased time since symptom onset 2, 3

Special Populations Requiring Caution

In patients with mild wheezing or chronic obstructive pulmonary disease, use a reduced starting dose of 12.5 mg orally of the short-acting, cardioselective metoprolol tartrate rather than completely avoiding beta-blockers. 1, 2

• Initially use low doses of beta-1 selective agents in patients with reactive airway disease 1, 2
• If concerns exist about tolerance, favor short-acting cardioselective agents like metoprolol tartrate over longer-acting formulations 1, 2

Administration Principles

Metoprolol must be administered on a scheduled, regular dosing regimen—never as needed (PRN)—because consistent plasma levels are essential for therapeutic benefit and abrupt discontinuation can precipitate rebound hypertension or worsening angina. 2, 3, 7

• Beta-blockers require steady-state plasma levels to achieve cardioprotection 3, 7
• Abrupt cessation is associated with 2.7-fold increased risk of 1-year mortality and can cause severe exacerbation of angina, myocardial infarction, and ventricular arrhythmias 2, 7
• When discontinuation is necessary, taper by 25-50% every 1-2 weeks 1, 2, 7

Monitoring Parameters

Monitor blood pressure and heart rate at each visit, targeting resting heart rate of 50-60 bpm, and assess for signs of worsening heart failure, bronchospasm, symptomatic bradycardia, or hypotension. 2, 3

• Watch for symptomatic bradycardia (HR <60 bpm with dizziness) and hypotension (systolic BP <100 mm Hg with symptoms) 2
• Listen for new or worsening bronchospasm, particularly in patients with any history of reactive airway disease 1, 2
• Clinical response may be delayed and require 2-3 months to become fully apparent 2

Common Pitfalls to Avoid

• Never prescribe metoprolol PRN for palpitations or anxiety—these require either scheduled beta-blocker therapy or alternative management 2, 7
• Never use IV metoprolol in patients with decompensated heart failure or hemodynamic instability—wait until clinical stabilization 1, 2, 3
• Never abruptly discontinue metoprolol—always taper to prevent rebound cardiovascular events 2, 3, 7
• Do not assume medium-range doses provide equivalent benefit to target doses—higher doses have demonstrated greater benefits in clinical trials, and there is little evidence that subtarget doses yield comparable survival benefits 1