What is the lowest dose of a beta (beta blocker) blocker?

Lowest Dose of Beta Blockers

Beta blockers should be initiated at very low doses, followed by gradual incremental increases if lower doses have been well tolerated, with specific starting doses varying by agent. 1

Initial Dosing Recommendations

• Treatment with a beta-blocker should be initiated at very low doses (one-tenth to one-twentieth of the doses generally used in angina or hypertension) 2
• The American Heart Association recommends starting with the lowest possible dose and gradually increasing if well tolerated 1
• For heart failure patients, beta-blockers should be started at very low doses with close monitoring of vital signs and symptoms during the uptitration period 1

Specific Starting Doses for Evidence-Based Beta Blockers

For heart failure, the three beta-blockers with proven mortality benefit have the following recommended initial doses:

• Bisoprolol: Start at 1.25 mg once daily 1
• Metoprolol succinate: Start at 12.5-25 mg once daily 1
• Carvedilol: Start at 3.125 mg twice daily 1

Titration Process

• Planned increments in the dose of a beta-blocker should be delayed until any side effects observed with lower doses have disappeared 1
• Dose adjustments should occur no more frequently than every 2 weeks to allow for stabilization 1
• Patients should be monitored closely for changes in vital signs and symptoms during the uptitration period 1
• Patients should weigh themselves daily to detect fluid retention that can accompany beta-blocker initiation 1

Special Populations Requiring Lower Doses

• Elderly patients should start at the lower end of the dosing range due to potential for increased sensitivity 3
• Patients with renal impairment may require lower doses as the plasma half-life can be increased approximately threefold in subjects with creatinine clearance less than 40 mL/min 4
• Patients with hepatic impairment may need lower doses as elimination is more variable and significantly slower, with plasma half-life ranging from 8.3 to 21.7 hours 4

Cautions and Contraindications

• Beta-blockers should not be initiated in patients with decompensated heart failure, requiring intravenous inotropic therapy 1
• For patients with reactive airway disease, a cardioselective beta-blocker at a reduced dose should be used 3, 5
• Bradycardia, including sinus pause, heart block, and cardiac arrest have occurred with metoprolol use; patients with first-degree atrioventricular block, sinus node dysfunction, or conduction disorders may be at increased risk 5

Target Doses and Efficacy

• Although starting doses are very low, clinicians should make every effort to achieve the target doses of beta-blockers shown to be effective in major clinical trials 1
• Studies have supported a dose-response relationship of beta-blockers with improved outcomes, suggesting that treating at less than the target dose may result in worse clinical outcomes 1
• Even a low dosage of beta-blockers can exert negative inotropic effects and may lead to a deterioration of hemodynamics in patients with heart failure 6

Management of Adverse Effects

• If bradycardia develops and is symptomatic, the dose of the beta-blocker should be reduced 3
• If fluid retention occurs, increase the dose of concomitantly administered diuretics until weight is restored to pretreatment levels 1
• Abrupt withdrawal of treatment with a beta-blocker can lead to clinical deterioration and should be avoided 1, 5