What is the minimum dose and duration of action of Propranolol (beta blocker)?

From the Guidelines

The minimum dose of propranolol is 2 mg/kg per day, and the duration of action is at least 6 months, as recommended by the most recent and highest quality study 1. The dose of propranolol can be adjusted based on the patient's response and the presence of comorbidities or adverse effects, with a maximum dose of 3 mg/kg per day.

• Key factors to consider when determining the dose and duration of propranolol include:
  • The patient's age and weight
  • The presence of comorbidities, such as PHACE syndrome
  • The occurrence of adverse effects, such as sleep disturbances or bronchial irritation
  • The risk of rebound growth after stopping the medication, which can occur in up to 25% of patients. The purpose of administering propranolol with or after feeding is to reduce the risk of hypoglycemia, which can be a significant adverse effect of the medication, especially in infants and children 1.
• Important considerations for clinicians when prescribing propranolol include:
  • Counseling patients on the importance of administering the medication with or after feeding
  • Holding doses at times of diminished oral intake or vomiting to reduce the risk of hypoglycemia
  • Evaluating patients for potential adverse effects, including sleep disturbances, bronchial irritation, and clinically symptomatic bradycardia and hypotension.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION General: Propranolol hydrochloride extended-release capsules provide propranolol hydrochloride in a sustained-release capsule for administration once daily. Hypertension: The usual initial dosage is 80 mg propranolol hydrochloride extended-release capsules once daily, whether used alone or added to a diuretic. Angina Pectoris: Starting with 80 mg propranolol hydrochloride extended-release capsules once daily, dosage should be gradually increased at three- to seven-day intervals until optimal response is obtained Migraine: The initial oral dose is 80 mg propranolol hydrochloride extended-release capsules once daily. Hypertrophic Subaortic Stenosis: The usual dosage is 80 to 160 mg propranolol hydrochloride extended-release capsules once daily.

The minimum dose of Propranolol is 80 mg once daily. The duration of action is at least 24 hours, as the drug is administered once daily. Key points:

• The dosage may be increased gradually to achieve optimal response.
• The time needed for full hypertensive response to a given dosage is variable and may range from a few days to several weeks.
• If treatment is to be discontinued, reduce dosage gradually over a period of a few weeks 2.

From the Research

Minimum Dose and Duration of Action of Propranolol

• The minimum dose of propranolol is not explicitly stated in the provided studies, but the dose range used in the studies varied from 40 to 320 mg per day 3, 4, 5.
• The duration of action of propranolol is also not explicitly stated, but one study found that a dose of 160 mg/day induced near-maximal cardiac blockade, and another study found that once-daily propranolol did not differ significantly from qid propranolol in terms of blood pressure control 4, 5.
• A study on the treatment of angina pectoris with propranolol found that the average optimum dosage was 500-800 mg a day, and that the dose-response relationship was logarithmic, with higher doses producing greater anti-anginal effects 6.
• Another study found that nonselective beta-blockers, including propranolol, lowered systolic and diastolic blood pressure by -10/-7 mmHg, and reduced heart rate by 12 beats per minute, but did not show a convincing graded dose-response in the recommended dose range 7.

Dose-Response Relationship

• The dose-response relationship of propranolol was found to be logarithmic in one study, with higher doses producing greater anti-anginal effects 6.
• Another study found that nonselective beta-blockers, including propranolol, did not show a convincing graded dose-response in the recommended dose range, but higher doses produced greater reductions in heart rate 7.
• A study on the treatment of hypertension with propranolol found that a dose of 160 mg/day induced near-maximal cardiac blockade, and that higher doses did not produce additional blood pressure lowering effects 4.

Clinical Usefulness

• Propranolol may be administered as a single daily dose to patients with hypertension whose blood pressure already has been controlled on a qid regimen 5.
• The use of beta-blocking agents, including propranolol, in angina pectoris is relatively safe, provided that contraindications are observed and treatment is commenced at a low dosage 6.
• The nitroglycerin test is of limited value in the assessment of beta adrenergic blockade in hypertensive patients, and propranolol in a dose of 160 mg/day induces near-maximal cardiac blockade 4.