Metoprolol Succinate Extended Release Tablets Usp Tablet

Z-MET-25 (Metoprolol Succinate Extended Release Tablets Usp Tablet)

Introduction
Metoprolol is a selective beta-1 blocker commonly employed as the succinate and tartrate derivatives depending if the formulation is designed to be of immediate release or extended release. The possibility of the generation of these formulations comes from the lower systemic bioavailability of the succinate derivative.

  Indications
Metoprolol is indicated for the treatment of angina, heart failure, myocardial infarction, atrial fibrillation, atrial flutter and hypertension

  Mechanism of action
Metoprolol is a beta-1-adrenergic receptor inhibitor specific to cardiac cells with negligible effect on beta-2 receptors. This inhibition decreases cardiac output by producing negative chronotropic and inotropic effects without presenting activity towards membrane stabilization nor intrinsic sympathomimetics
  Dosage
As prescribed by the physician.
  Pharmacology
Absorption

When metoprolol is administered orally, it is almost completely absorbed in the gastrointestinal tract.1 The maximum serum concentration is achieved 20 min after intravenous administration and 1-2 hours after oral administration. The bioavailability of metoprolol is of 100% when administered intravenously and when administered orally it presents about 50% for the tartrate derivative and 40% for the succinate derivative. 
Distribution
The reported volume of distribution of metoprolol is 4.2 L/kg
Excretion
Metoprolol is mainly excreted via the kidneys. From the eliminated dose, less than 5% is recovered unchanged
  Precautions
Check with your doctor right away if you are having chest pain or discomfort, dilated neck veins, extreme fatigue, irregular breathing or heartbeat, shortness of breath, swelling of the face, fingers, feet, or lower legs, or weight gain. Do not suddenly stop taking this medicine without first checking with your doctor
  Contraindications
• pheochromocytoma
• diabetes
• low blood sugar
• depression
• myasthenia gravis, a skeletal muscle disorder
• complete heart block
• second degree atrioventricular heart block
• sick sinus syndrome
• sinus bradycardia
• sudden and serious symptoms of heart failure called acute decompensated heart failure
• Raynaud's phenomenon, a condition where blood vessels constrict too much with coldness or stress
• peripheral vascular disease