What is the typical dosage and usage of Propranolol (beta-blocker) for treating hypertension, angina, and arrhythmias?

Propranolol Dosing and Usage

Hypertension

For hypertension, start with propranolol extended-release 80 mg once daily, titrating to 120-160 mg once daily for maintenance, with a maximum of 640 mg daily if needed. 1

• The FDA-approved initial dose is 80 mg of extended-release propranolol once daily, whether used alone or combined with a diuretic 1
• Usual maintenance dosage ranges from 120-160 mg once daily, though some patients may require up to 640 mg daily 1
• Full hypertensive response to a given dosage is variable and may take anywhere from a few days to several weeks 1
• When combined with thiazide diuretics, propranolol (up to 480 mg/day) achieves blood pressure control in over 80% of patients with mild to moderately severe hypertension 2

Critical Pre-Treatment Assessment

Before initiating propranolol, screen for absolute contraindications: 3

• Second or third-degree heart block
• Decompensated heart failure
• Asthma or obstructive airway disease
• Cardiogenic shock
• Sinus node dysfunction without pacemaker

Perform baseline cardiovascular assessment including heart rate, blood pressure measurement, and cardiovascular examination with auscultation 3

Angina Pectoris

For angina, begin with 80 mg extended-release propranolol once daily and gradually increase at 3-7 day intervals until optimal response is achieved, with an average optimal dose of 160 mg once daily. 1

• The average optimal dosage for angina appears to be 160 mg once daily, though individual patients may respond at any dosage level 1
• Dosages exceeding 320 mg per day have not been established as safe or effective for angina 1
• For severe angina (NYHA class III or IV), the mean effective daily dose in long-term studies was 255 mg, with some patients requiring 500-800 mg daily for optimal control 4, 5
• A dose-dependent anti-anginal effect exists, with progressive reduction in angina attacks as dosage increases logarithmically 4

Efficacy and Safety Considerations

• 84% of patients per year achieve 50% or more reduction in anginal episodes with propranolol 5
• Patients achieving less than 50% reduction in angina have a nearly four-fold greater mortality rate compared to those with 50% or more reduction 5
• No evidence of tachyphylaxis develops with long-term use 5
• If discontinuing treatment, reduce dosage gradually over several weeks to prevent rebound angina, myocardial infarction, or ventricular arrhythmias 1, 3

High-Risk Features Requiring Caution

Relative contraindications for propranolol in angina include: 5

• Previous history of congestive heart failure
• Cardiothoracic ratio greater than 0.5 on chest X-ray
• All patients with cardiothoracic ratio >0.5 developed heart failure within the first 3 years of therapy 5

Cardiac Arrhythmias

For arrhythmias requiring immediate control, administer 5 mg IV bolus over 1-2 minutes, repeatable every 5 minutes up to a maximum total dose of 15 mg. 3

• IV propranolol is indicated for stable narrow-complex tachycardias unresponsive to adenosine or vagal maneuvers, and rate control in atrial fibrillation or atrial flutter 3
• Continuous monitoring during IV administration must include heart rate, blood pressure, and auscultation for new rales or bronchospasm 3
• Have a defibrillator readily available when administering IV propranolol 3

Critical Contraindications for IV Administration

Do not administer IV propranolol in patients with: 3

• Second or third-degree heart block
• Active asthma or reactive airway disease
• Pre-excited atrial fibrillation
• Decompensated heart failure

Important Dosing Considerations

Extended-Release vs. Immediate-Release Formulations

• Propranolol extended-release capsules are not a simple mg-for-mg substitute for immediate-release tablets 1
• Extended-release formulations have different kinetics and produce lower blood levels 1
• Retitration may be necessary when switching formulations, especially to maintain effectiveness at the end of the 24-hour dosing interval 1
• Extended-release propranolol has a prolonged terminal half-life (8-11 hours) compared to immediate-release formulations 6

Administration Guidelines

• Administer propranolol with food to reduce the risk of hypoglycemia 3
• Hold doses during times of diminished oral intake or vomiting 3
• Lower doses may be required for elderly patients due to altered pharmacokinetics 3

Critical Safety Warnings

Abrupt Discontinuation

Never abruptly discontinue propranolol after chronic use—taper gradually over several weeks to prevent rebound hypertension, tachycardia, angina, myocardial infarction, or ventricular arrhythmias. 3, 1

Common Adverse Effects

Monitor for: 3

• Hypotension and bradycardia (especially during dose escalation)
• Fatigue and dizziness
• Cold extremities
• Potential worsening of heart failure
• Masking of hypoglycemia symptoms in diabetic patients

Drug Interactions

Avoid routine combination with non-dihydropyridine calcium channel blockers (diltiazem, verapamil) due to increased risk of bradycardia and heart block 3

Monitoring Requirements

• No routine vital sign monitoring required between appointments if the patient is stable and asymptomatic 3
• Routine blood work (CBC, renal, liver, thyroid function) is not required before starting propranolol in otherwise healthy adults 3
• ECG and echocardiogram are only needed in selected cases with cardiac concerns 3
• Monitor specifically for hypotension, bradycardia, and signs of worsening heart failure during dose escalation 3