Metoprolol Tartrate for Injection 5 mL Single-Dose Vials 10/Box (RX)

Metoprolol Tartrate for Injection is used primarily to manage acute episodes of hypertension and to control heart rate in patients experiencing tachycardia or other arrhythmias. It is a beta-blocker that works by blocking beta-adrenergic receptors, reducing heart rate, cardiac output, and blood pressure. This formulation is particularly useful in emergency settings, such as after a heart attack, to reduce the heart's workload and oxygen demand. Administered intravenously, it offers rapid action in stabilizing cardiac conditions.

Metoprolol Tartrate Injection is a beta-blocker medication provided by Pfizer Injectables, intended for intravenous use. It is primarily used for the rapid control of heart rate and blood pressure in acute settings, such as during a myocardial infarction (heart attack) or to manage arrhythmias and severe hypertension. The formulation is available in single-dose vials of 5 mL, and each box contains 10 vials. 

Details and Features

Active Ingredient: Metoprolol Tartrate
Concentration: Usually formulated to provide a specified amount of metoprolol tartrate per mL (check specific packaging for precise details).
Volume: 5 mL per vial
Packaging: 10 single-dose vials per box
Administration Route: Intravenous (IV) injection
Indications: Rapid treatment of acute myocardial infarction, control of heart rate in tachyarrhythmias (like atrial fibrillation or flutter), acute hypertension, and in certain cases, stable heart failure as adjunct therapy.

Mechanism of Action

Metoprolol Tartrate is a selective beta-1 adrenergic receptor blocker, primarily affecting cardiac tissues. By inhibiting the action of catecholamines (such as adrenaline) on beta-1 receptors, metoprolol reduces heart rate, cardiac output, and blood pressure. It decreases myocardial oxygen demand by lowering heart rate and contractility, which is particularly beneficial during heart attacks as it helps minimize heart muscle damage. Additionally, it can decrease electrical activity in the heart, helping to manage arrhythmias.

Warnings

• Heart Block and Bradycardia: Contraindicated in patients with significant bradycardia or advanced heart block unless a pacemaker is in place.
  
• Hypotension: Use caution in patients with low blood pressure, as it can further decrease blood pressure.
  
• Asthma and COPD: Although selective, beta-blockers can affect beta-2 receptors at higher doses, potentially exacerbating bronchospasms in susceptible individuals.
  
• Acute Heart Failure: Initiation or dosage increments in acute heart failure should be done cautiously, as beta-blockers can initially cause worsening symptoms.
  
• Abrupt Withdrawal: Sudden discontinuation can lead to rebound tachycardia, hypertension, or even precipitate angina or myocardial infarction. Dosing should typically be tapered.

Side Effects

While metoprolol tartrate is effective, it can have side effects, especially when used acutely and intravenously:

Common Side Effects:

• Fatigue or lethargy
  
• Dizziness or lightheadedness
  
• Bradycardia (slow heart rate)
  
• Hypotension

Serious Side Effects:

• Severe bradycardia or heart block
  
• Heart failure exacerbation
  
• Bronchospasm in individuals with a history of respiratory disorders
  
• Cardiogenic shock in susceptible patients

Other Considerations:

Monitoring: During administration, continuous monitoring of cardiac function (heart rate, ECG) and blood pressure is advisable. Adjustments to dose or infusion rate may be necessary based on the patient's response.
Drug Interactions: Metoprolol may interact with other medications, such as other antihypertensives, antiarrhythmics, and certain antidepressants, necessitating a comprehensive medication review.

Metoprolol Tartrate for Injection is a potent medication used in critical care and emergency settings, offering rapid management of cardiovascular conditions when oral administration is not feasible. Its use should be overseen by healthcare professionals to ensure safe administration and effective therapeutic outcomes.