Metoprolol is a cardioselective β1-adrenergic blocking agent used for acute myocardial infarction (MI), heart failure, angina pectoris and mild to moderate hypertension. It may also be used for supraventricular and tachyarrhythmias and prophylaxis for migraine headaches. Metoprolol is structurally similar to bisoprolol, acebutolol and atenolol in that it has two substituents in the para position of the benzene ring. The β1-selectivity of these agents is thought to be due in part to the large substituents in the para position. At low doses, metoprolol selectively blocks cardiac β1-adrenergic receptors with little activity against β2-adrenergic receptors of the lungs and vascular smooth muscle. Receptor selectivity decreases with higher doses. Unlike propranolol and pindolol, metoprolol does not exhibit membrane-stabilizing or intrinsic sympathomimetic activity. Membrane-stabilizing effects are only observed at doses much higher than those needed for β-adrenergic blocking activity. Metoprolol possesses a single chiral centre and is administered as a racemic mixture.
Metoprolol, a competitive, beta1-selective (cardioselective) adrenergic antagonist, is similar to atenolol in its moderate lipid solubility, lack of intrinsic sympathomimetic activity (ISA), and weak membrane stabilizing activity (MSA).
LD50=5500 mg/kg (orally in rats), toxic effects include bradycardia, hypotension, bronchospasm, and cardiac failure. LD50=2090 mg/kg (orally in mice)
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Drug: Metoprolol
Strength: 25 Mg / 50 Mg
Pill Imprint: M 424
Color: Peach
Shape: Round
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Drug: Metoprolol
Strength: 25 Mg / 100 Mg
Pill Imprint: M 434
Color: Orange
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Drug: Metoprolol
Strength: 25 Mg / 50 Mg
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Drug: Metoprolol
Strength: 50 Mg / 100 Mg
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Drug: Metoprolol
Strength: 25 Mg / 50 Mg
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Drug: Metoprolol
Strength: 25 Mg / 100 Mg
Pill Imprint: L 232
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Drug: Metoprolol
Strength: 25 Mg / 100 Mg
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Drug: Metoprolol
Strength: 25 Mg / 50 Mg
Pill Imprint: SANDOZ 909 909
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Drug: Metoprolol
Strength: 25 Mg / 100 Mg
Pill Imprint: S 368
Color: Pink
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Drug: Metoprolol
Strength: 50 Mg / 100 Mg
Pill Imprint: S 369
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Drug: Metoprolol
Strength: 50 Mg / 100 Mg
Pill Imprint: L 231
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Drug: Metoprolol
Strength: 25 Mg
Pill Imprint: M B
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Drug: Metoprolol
Strength: 100 Mg
Pill Imprint: 167
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Drug: Metoprolol
Strength: 50 Mg
Pill Imprint: 166
Color: White
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Drug: Metoprolol
Strength: 200 Mg
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Drug: Metoprolol
Strength: 100 Mg
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Drug: Metoprolol
Strength: 50 Mg
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Strength: 100 Mg
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Drug: Metoprolol
Strength: 50 Mg
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Strength: 100 Mg
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Drug: Metoprolol
Strength: 100 Mg
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Drug: Metoprolol
Strength: 25 Mg
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Drug: Metoprolol
Strength: 25 Mg
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Drug: Metoprolol
Strength: 50 Mg
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Drug: Metoprolol
Strength: 200 Mg
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Drug: Metoprolol
Strength: 50 Mg
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Drug: Metoprolol
Strength: 25 Mg
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Strength: 200 Mg
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Drug: Metoprolol
Strength: 100 Mg
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Drug: Metoprolol
Strength: 50 Mg
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Strength: 200 Mg
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Strength: 200 Mg
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Drug: Metoprolol
Strength: 25 Mg
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Strength: 200 Mg
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Drug: Metoprolol
Strength: 100 Mg
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Drug: Metoprolol
Strength: 200 Mg
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Drug: Metoprolol
Strength: 37.5 Mg
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Drug: Metoprolol
Strength: 25 Mg
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Drug: Metoprolol
Strength: 50 Mg
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Drug: Metoprolol
Strength: 200 Mg
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Drug: Metoprolol
Strength: 100 Mg
Pill Imprint: 71 71 GEIGY
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Drug: Metoprolol
Strength: 50 Mg
Pill Imprint: LOPRESSOR 458 458
Color: Pink
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Drug: Metoprolol
Strength: 100 Mg
Pill Imprint: LOPRESSOR 459 459
Color: Blue
Shape: Capsule-shape
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