What is the lowest dose of propranolol (beta-blocker)?

Lowest Dose of Propranolol

The lowest therapeutic dose of propranolol is 0.5 mg/kg/day, which is used in specific populations such as patients with suspected PHACES syndrome, preterm infants, and those with comorbidities that increase hypoglycemia risk. 1

General Dosing Guidelines

Standard Dosing

• Starting dose for most patients is 1 mg/kg/day divided into three doses 1
• Maintenance dose for uncomplicated patients is 2 mg/kg/day 1
• Maximum dose for non-responders is 3 mg/kg/day 1
• Most studies support dosing between 2-3 mg/kg/day for optimal efficacy 1

Special Populations Requiring Lower Doses

• Patients with suspected PHACES syndrome should start at 0.5 mg/kg/day 1
• Preterm infants or those with low weight should start at 0.5 mg/kg/day 1
• Patients with comorbidities that increase hypoglycemia risk (hyperinsulinism, history of hypoglycemia) should start at 0.5 mg/kg/day 1
• Patients with progressive ulceration while on therapy may require dose reduction 1
• Patients experiencing adverse effects like sleep disturbances may benefit from lower doses 1

Dosing Considerations by Age

• Infants younger than 4 weeks of age require more cautious dosing, typically starting at 0.5 mg/kg/day 1
• Recent research suggests propranolol can be safely used in infants less than 5 weeks corrected age at doses of 1-3 mg/kg/day, but requires careful monitoring 2
• Some studies have shown efficacy with low-dose propranolol (0.5 mg/kg/day initially, titrated up to 1.5 mg/kg/day) for infantile hemangiomas 3

Administration Guidelines

• Propranolol should be administered with or after feeding to reduce hypoglycemia risk 1
• Doses should be held during times of diminished oral intake or vomiting 1
• Minimum time interval between dose increases should be 24 hours 1
• For patients with PHACES syndrome, administering the drug 3 times daily helps minimize abrupt blood pressure changes 1

Monitoring Requirements

• Patients at higher risk (preterm, low weight, <4 weeks age, comorbidities) require admission for 2-4 hours on initiation and for dose increments >0.5 mg/kg/day 1
• Heart rate and blood pressure should be measured before the first dose and every 30 minutes for 2-4 hours after the first dose in high-risk patients 1
• Blood glucose monitoring is only needed in patients at risk for hypoglycemia 1

Common Pitfalls and Caveats

• Dosing errors can occur with different propranolol formulations; the 5 mg/5 mL preparation is recommended as least likely to cause dosing errors 1
• Abrupt discontinuation of propranolol can lead to rebound growth of infantile hemangiomas, though guidelines suggest it is safe to stop treatment abruptly 1
• Propranolol should be stopped if the child becomes unwell with reduced feeding until normal feeding resumes 1
• Rebound growth is more likely if therapy is discontinued before 12 months of age, particularly before 9 months 1