What is the dosage of propranolol?

Propranolol Dosage Guidelines

The appropriate dosage of propranolol varies by indication, with standard maintenance doses ranging from 80-240 mg daily for most conditions, with specific titration protocols based on the condition being treated. 1

Dosing by Indication

Infantile Hemangioma

• Starting dose: 1 mg/kg/day 2
• Maintenance dose: 2 mg/kg/day for uncomplicated patients 2
• Maximum dose: 3 mg/kg/day for non-responders 2
• Administration: Divided into 2-3 daily doses 2
• Special populations:
  • For PHACES syndrome: Start at 0.5 mg/kg/day 2
  • For premature/low weight infants: Use more cautious dosing 2

Hypertension

• Initial dose: 80 mg once daily (extended-release) 1
• Maintenance dose: 120-160 mg once daily 1
• Maximum dose: Up to 640 mg may be required in some cases 1
• Titration: Increase gradually until adequate blood pressure control is achieved 1

Angina Pectoris

• Starting dose: 80 mg once daily (extended-release) 1
• Maintenance dose: Average optimal dose is 160 mg once daily 1
• Maximum dose: 320 mg daily (safety not established beyond this) 1
• Titration: Increase gradually at 3-7 day intervals 1

Migraine Prophylaxis

• Initial dose: 80 mg once daily (extended-release) 1
• Effective dose range: 160-240 mg once daily 3, 1
• Duration: 4-6 weeks trial to assess efficacy 1

Hypertrophic Subaortic Stenosis

• Usual dosage: 80-160 mg once daily (extended-release) 1

Administration Considerations

1. Extended-release formulations:

   • Not a simple mg-for-mg substitute for immediate-release tablets 1
   • Administered once daily 1
   • Retitration may be necessary when switching from immediate-release 1

2. Infantile hemangioma administration:

   • Administer with or after feeding to reduce hypoglycemia risk 2
   • Hold doses during times of diminished oral intake or vomiting 2
   • Use 5 mg/5 mL preparation 2

3. Discontinuation:

   • For angina: Reduce dosage gradually over several weeks 1
   • For infantile hemangioma: Can be stopped abruptly at 1 year of age 2
   • For migraine: May need gradual withdrawal over several weeks 1

Monitoring and Precautions

• Contraindications:

  • Hypoglycemic episodes (recent or ongoing) 2
  • Second or third-degree heart block 2
  • Hypersensitivity to propranolol 2
  • Asthma or obstructive airway disease 2

• Pretreatment assessment:

  • Cardiovascular and respiratory examination 2, 3
  • ECG and ECHO in selected cases 2

• Common side effects:

  • Hypotension, bradycardia 2
  • Precipitation of heart failure 2
  • Sleep disturbances 2

Clinical Pearls

• Lower doses (80-160 mg daily) may provide most of the antihypertensive effect, with higher doses offering minimal additional benefit 4
• For angina, plasma levels >100 ng/ml are associated with 70-80% reduction in exercise-induced tachycardia 5
• Propranolol-hydralazine combinations may be more effective than either component alone for hypertension 6
• Low doses of propranolol (close to 1 mg/kg/day) may be effective for migraine prophylaxis in many patients 7

Remember that dosage should be carefully monitored and adjusted based on clinical response and tolerance, particularly in patients with comorbidities or at risk for adverse effects.