Does metoprolol (beta blocker) affect blood pressure?

From the Guidelines

Yes, metoprolol does affect blood pressure by lowering it. Metoprolol is a beta-blocker medication that works by blocking the effects of adrenaline on your heart and blood vessels, causing your heart to beat more slowly and with less force, which reduces blood pressure. It's commonly prescribed for high blood pressure (hypertension), angina, and heart failure, typically at doses ranging from 25-100 mg once or twice daily depending on the formulation (immediate or extended-release) 1.

Key Points to Consider

• When taking metoprolol, it's essential to take it regularly as prescribed, even if you feel well, and never stop suddenly as this can cause rebound high blood pressure or worsening of underlying heart conditions.
• Common side effects may include fatigue, dizziness, and slow heart rate.
• Metoprolol lowers blood pressure by reducing cardiac output and the release of renin from the kidneys, ultimately decreasing the workload on your heart and improving blood flow through your blood vessels 1.
• The choice of beta blocker for an individual patient is based primarily on pharmacokinetic and side effect criteria, as well as on physician familiarity 1.
• Patients with marked first-degree AV block, any form of second- or third-degree AV block, a history of asthma, severe LV dysfunction or HF, or at high risk for shock should not receive beta blockers on an acute basis 1.

Important Considerations for Metoprolol Use

• Metoprolol can be given intravenously in 5-mg increments by slow intravenous administration, repeated every 5 min for a total initial dose of 15 mg 1.
• Oral therapy can be initiated 15 min after the last intravenous dose at 25 to 50 mg every 6 h for 48 h, with a maintenance dose of up to 100 mg twice daily 1.
• Carvedilol, another beta blocker, can reduce mortality and reinfarction when given to patients with recent MI and LV dysfunction, and its use may be preferred in certain cases due to its additional alpha-adrenergic blocking effects 1.

From the FDA Drug Label

CLINICAL PHARMACOLOGY Mechanism of Action Metoprolol is a beta 1-selective (cardioselective) adrenergic receptor blocker. ... Clinical pharmacology studies have demonstrated the beta-blocking activity of metoprolol, as shown by ... (2) reduction of systolic blood pressure upon exercise Hypertension The mechanism of the antihypertensive effects of beta-blocking agents has not been fully elucidated However, several possible mechanisms have been proposed: (1) competitive antagonism of catecholamines at peripheral (especially cardiac) adrenergic neuron sites, leading to decreased cardiac output; In several studies of patients with acute myocardial infarction, intravenous followed by oral administration of metoprolol caused a reduction in heart rate, systolic blood pressure and cardiac output

Metoprolol effects on blood pressure:

• Metoprolol reduces systolic blood pressure upon exercise.
• The drug causes a reduction in systolic blood pressure in patients with acute myocardial infarction.
• Metoprolol is used to treat hypertension, and its mechanism of action includes decreasing cardiac output, which leads to a reduction in blood pressure. 2

From the Research

Effect of Metoprolol on Blood Pressure

• Metoprolol has been shown to significantly decrease both systolic and diastolic blood pressure in patients with hypertension 3, 4, 5.
• Studies have demonstrated that metoprolol can effectively lower blood pressure in various patient populations, including the elderly 4 and those with mild to moderate hypertension 3, 5.
• The maximum effect of metoprolol on blood pressure has been observed to occur after approximately three weeks of treatment 3.
• Metoprolol has been found to be well-tolerated, with side effects occurring in a relatively small percentage of patients 3, 4, 5.

Comparison with Other Antihypertensive Agents

• Metoprolol has been compared to other antihypertensive agents, such as amlodipine, and has been shown to have a greater effect on lowering diastolic blood pressure and heart rate 5.
• The combination of metoprolol with other agents, such as ACE inhibitors, has been found to be effective in lowering blood pressure and improving cardiovascular outcomes 6, 7.
• Studies have also shown that metoprolol and ACE inhibitors are equally effective as second-line therapy for patients whose blood pressure is not controlled with a thiazide diuretic alone 7.