Propranolol Starting Dose for Sinus Tachycardia and Hypertension
For sinus tachycardia with hypertension, start propranolol immediate-release at 40 mg twice daily (80 mg total daily dose), or propranolol extended-release 80 mg once daily, then titrate upward based on response. 1, 2, 3
Pre-Treatment Assessment Required
Before initiating propranolol, you must screen for absolute contraindications: 4, 2
- Second or third-degree heart block 4, 2
- Decompensated heart failure or cardiogenic shock 4, 2
- Asthma or obstructive airway disease 4, 2
- Sinus bradycardia or hypotension 4, 2
- Known hypersensitivity to propranolol 2
Baseline assessment should include heart rate, blood pressure measurement, and cardiovascular examination with auscultation. 1 Routine ECG or laboratory work is not required in otherwise healthy patients without cardiac concerns. 1
Initial Dosing Strategy
Immediate-release formulation: Start with 40 mg twice daily (80 mg total daily). 4, 1 This lower starting dose minimizes risk of precipitating heart failure or excessive bradycardia, which is most likely when first initiating beta-blockade. 5
Extended-release formulation: Start with 80 mg once daily. 1, 3 The FDA label specifies this as the standard initial dose for hypertension. 3
The rationale for starting at 80 mg daily total dose is that research demonstrates significant blood pressure reduction (11 mm Hg systolic, 9 mm Hg diastolic) occurs at this dose, with most antihypertensive effect achieved by 80-160 mg daily. 6 Higher doses provide diminishing additional benefit for blood pressure control. 6
Titration Protocol
Increase dose every 3-7 days based on response: 3, 5
- Week 1-2: 80 mg daily (40 mg BID or 80 mg ER once daily) 1, 3
- Week 2-3: 120 mg daily (60 mg BID or 120 mg ER once daily) if inadequate response 1, 3
- Week 3-4: 160 mg daily (80 mg BID or 160 mg ER once daily) - this is the usual maintenance dose 4, 1, 3
- Beyond 160 mg: Can increase further if needed, up to maximum 640 mg daily, though this is rarely necessary 3, 6
For sinus tachycardia specifically, beta-blockade is extremely effective for symptomatic relief. 2 The goal is to reduce resting heart rate to approximately 55-60 beats per minute, provided this doesn't cause side effects. 5
Monitoring During Titration
- Hypotension - most common at initiation 4, 1
- Bradycardia - especially during dose escalation 4, 1
- Worsening heart failure - greatest risk occurs when first starting, even at low doses 5
- Bronchospasm - in patients with unrecognized reactive airway disease 4
- Fatigue, dizziness, cold extremities 1
No routine vital sign monitoring between appointments is required if the patient remains stable and asymptomatic. 1
Critical Safety Considerations
Never abruptly discontinue propranolol after chronic use, as this precipitates rebound hypertension, tachycardia, or angina. 1 Taper gradually over several weeks when discontinuing. 1, 3
Avoid combining with non-dihydropyridine calcium channel blockers (diltiazem, verapamil) due to increased risk of severe bradycardia and heart block. 4, 1
In diabetic patients, propranolol may mask hypoglycemia symptoms. 1 Counsel patients accordingly.
Elderly patients may require lower doses due to altered pharmacokinetics. 1
Special Circumstances
If hypertensive emergency: Use IV labetalol (combined alpha/beta blocker) 0.3-1.0 mg/kg slow IV injection (maximum 20 mg) every 10 minutes instead of propranolol, as it provides more controlled blood pressure reduction. 1 IV propranolol (0.5-1 mg over 1 minute, up to 0.1 mg/kg total) can be used but carries higher risk. 4
If acute symptomatic tachycardia with hemodynamic instability: Consider IV metoprolol 2.5-5 mg over 2 minutes (up to 3 doses) or IV esmolol 500 mcg/kg bolus followed by infusion, as these have more predictable pharmacokinetics than IV propranolol. 4
Expected Timeline for Response
Full antihypertensive response to a given dose is variable and may take several days to weeks. 3 For sinus tachycardia, heart rate reduction occurs within hours of the first dose. 7 Most therapeutic benefit occurs at plasma levels of 30 ng/ml, typically achieved with 80-160 mg daily. 8