From the Guidelines
Metoprolol tartrate should be dosed at 25 to 50 mg every 6 to 12 hours orally, then transitioned over the next 2 to 3 days to twice-daily dosing of metoprolol tartrate or to daily metoprolol succinate, with a target daily dose of 200 mg as tolerated 1.
Key Considerations
- The dosing of metoprolol tartrate may vary depending on the specific indication, such as hypertension, angina, heart failure, or post-myocardial infarction.
- For heart failure, the initial dose should be lower, at 12.5-25 mg twice daily, and titrated slowly 1.
- Metoprolol tartrate should be taken with food consistently to improve absorption and reduce gastrointestinal side effects.
- Dose adjustments are necessary for patients with hepatic impairment, and the medication should not be abruptly discontinued due to the risk of rebound hypertension or angina.
Common Side Effects
- Fatigue
- Dizziness
- Bradycardia These side effects often improve with continued use or dose adjustment.
Mechanism of Action
Metoprolol works by blocking beta-1 adrenergic receptors in the heart, reducing heart rate, contractility, and blood pressure.
Clinical Guidelines
The American College of Cardiology/American Heart Association (ACC/AHA) guidelines recommend metoprolol tartrate as a first-line treatment for various cardiovascular conditions, including hypertension, angina, and heart failure 1.
From the FDA Drug Label
DOSAGE & ADMINISTRATION Myocardial Infarction Early Treatment During the early phase of definite or suspected acute myocardial infarction, initiate treatment with metoprolol tartrate as soon as possible after the patient’s arrival in the hospital. Such treatment should be initiated in a coronary care or similar unit immediately after the patient’s hemodynamic condition has stabilized Begin treatment in this early phase with the intravenous administration of three bolus injections of 5 mg of metoprolol tartrate injection each; give the injections at approximately 2-minute intervals. During the intravenous administration of metoprolol tartrate injection, monitor blood pressure, heart rate, and electrocardiogram In patients who tolerate the full intravenous dose (15 mg), initiate metoprolol tartrate tablets, 50 mg every 6 hours, 15 minutes after the last intravenous dose and continued for 48 hours. Thereafter, the maintenance dosage is 100 mg orally twice daily Start patients who appear not to tolerate the full intravenous on metoprolol tartrate tablets either 25 mg or 50 mg every 6 hours (depending on the degree of intolerance) 15 minutes after the last intravenous dose or as soon as their clinical condition allows. The dosing for Metoprolol (Lopressor) tartrate is as follows:
- Initial Intravenous Dose: 3 bolus injections of 5 mg each, given at 2-minute intervals
- Initial Oral Dose (after intravenous dose): 50 mg every 6 hours for 48 hours
- Maintenance Oral Dose: 100 mg orally twice daily
- Alternative Oral Dose (for patients who do not tolerate full intravenous dose): 25 mg or 50 mg every 6 hours 2
From the Research
Dosing Information for Metoprolol (Lopressor) Tartrate
- The dosing for Metoprolol tartrate can vary depending on the condition being treated, as seen in studies 3, 4, 5, 6, 7.
- For patients with chronic heart failure, treatment with metoprolol controlled-release/extended-release (CR/XL) was initiated at a low dosage of 12.5 to 25 mg once daily and gradually increased at 2-weekly intervals until the target dosage (200 mg once daily) or maximal tolerated dosage had been attained 3.
- In the treatment of hypertension, a fixed combination of metoprolol tartrate 100 mg and chlorthalidone 25 mg was used as a single daily dose 5.
- A comparison of a controlled release (CR/ZOK) formulation of metoprolol, once daily, with conventional metoprolol tablets, twice daily, in mild to moderate hypertension, used a starting dose of 100 mg od in the CR/ZOK group and 50 mg bid in the tablet group, with the dose increased to 200 mg od and 100 mg bid, respectively, in nonresponders 6.
- Metoprolol administered once daily in the treatment of hypertension used doses of 100 mg and 200 mg conventional tablets or 200 mg slow-release tablets (Durules) once daily 7.
Key Findings
- The studies suggest that metoprolol tartrate can be effective in reducing blood pressure and improving clinical outcomes when used at a variety of dosages 3, 4, 5, 6, 7.
- The dosing regimen may need to be adjusted based on individual patient response and tolerance 3, 6.
- Metoprolol tartrate can be used in combination with other medications, such as diuretics, to enhance its therapeutic effects 4, 5, 6.