What is the maximum 24‑hour dose of metoprolol for an adult with anxiety‑related tachycardia?

Maximum 24-Hour Dose of Metoprolol for Anxiety-Related Tachycardia

For anxiety-related tachycardia, the maximum 24-hour dose of metoprolol tartrate is 400 mg daily (200 mg twice daily) and for metoprolol succinate extended-release is 400 mg once daily. 1

Formulation-Specific Maximum Dosing

Metoprolol Tartrate (Immediate-Release)

• Maximum dose: 200 mg twice daily (400 mg total per day) 1
• Initial dosing: 25 mg twice daily 1
• Maintenance range: 100-200 mg twice daily 1
• Titration interval: Every 1-2 weeks based on heart rate and blood pressure response 2

Metoprolol Succinate (Extended-Release)

• Maximum dose: 400 mg once daily 1
• Initial dosing: 50 mg once daily 1
• Maintenance range: 50-400 mg once daily 1
• Titration interval: Every 1-2 weeks as tolerated 2

Clinical Context for Anxiety-Related Tachycardia

While the guidelines primarily address supraventricular tachycardia and atrial fibrillation, the dosing parameters apply to anxiety-related tachycardia as beta-blockers reduce sympathetic drive regardless of etiology. 1

Target heart rate: Aim for resting heart rate of 50-60 beats per minute unless limiting side effects occur. 2

Absolute Contraindications Before Initiating Therapy

You must exclude these conditions before starting metoprolol at any dose:

• AV block greater than first degree or SA node dysfunction (without pacemaker) 1
• Decompensated systolic heart failure 1
• Hypotension (systolic BP <100 mmHg with symptoms) 2
• Reactive airway disease or severe asthma 1
• Cardiogenic shock 1

Monitoring Parameters During Titration

• Blood pressure and heart rate at each visit 2
• Watch for symptomatic bradycardia (HR <60 bpm with dizziness or lightheadedness) 2
• Assess for hypotension (systolic BP <100 mmHg with symptoms like dizziness or blurred vision) 2
• Listen for new or worsening bronchospasm, particularly with any history of reactive airway disease 2

Common Adverse Effects

The most frequent side effects include:

• Hypotension 1
• Bradycardia 1
• Bronchospasm 1
• Fatigue (may appear within 2-3 weeks) 2

Critical Warnings About Discontinuation

Never abruptly discontinue metoprolol. Abrupt cessation can cause severe exacerbation of angina, myocardial infarction, ventricular arrhythmias, and has been associated with 50% mortality in one study. 2 If discontinuation is necessary, reduce the dose by 25-50% every 1-2 weeks. 2

Practical Dosing Algorithm

1. Start low: Begin with metoprolol tartrate 25 mg twice daily or metoprolol succinate 50 mg once daily 1, 2
2. Titrate gradually: Increase dose every 1-2 weeks based on heart rate response 2
3. Monitor closely: Check BP and HR at each visit during titration 2
4. Target dose: Titrate to symptom control, targeting resting HR 50-60 bpm 2
5. Maximum limits: Do not exceed 200 mg twice daily (tartrate) or 400 mg once daily (succinate) 1

Special Considerations

Drug interactions: Use caution with other medications that cause bradycardia or AV nodal blockade, including digoxin, diltiazem, verapamil, or amiodarone. 1

Renal impairment: No dose adjustment required 3

Hepatic impairment: Initiate at low doses with cautious gradual titration, as metoprolol levels increase substantially with liver dysfunction 3