Metoprolol (Lopressor)

  1. Class:
    Selective Beta-Blocker
  2. Description:
    Beta-antagonist that blocks both beta one and beta two adrenergic receptors. Selective for Beta one receptors
  3. Mechanism of Action
    Causes reduction in heart rate, systolic blood pressure, and cardiac output following administration because of its selective effects for Beta one adrenergic receptors. Inhibits Tachycardia (Especially after acute MI)
  4. Onset of Action:
    • Onset: Immediate
    • Peak: 20 minutes
    • Duration: 13-19 hours
    • Half-Life: 3-4 hours
  5. Indications:
    Used in pts with suspected or definitive acute MI who are hemodynamically stable, A-Fib, SVT’s not responding to vagal or Adenocard
  6. Contraindications:
    Heart rate less than 45 BPM, a systolic BP less than 100 mmHg, or CHF, Pt showing early or late signs of shock, hx of asthma or bronchospastic disease, first degree heart block (PR interval greater than .24 sec), second and third degree heart block
  7. Precautions
    • Monitor BP, Pulse, ECG, RR.
    • Discontinue use with s/s of CHF, bradycardia, shock, heart block, bronchospasm
  8. Side Effects
    • Bradycardia,
    • Bronchospasm
    • CHF
    • Depression
    • dyspnea
    • Heart Block
    • Hypotension
    • Lethargy
    • Weakness
    • Wheezing
  9. Adult Dose
    Initial bolus 5mg, second IV injection after 2 mins 5 mg(if vitals are stable), third IV injection after 2 mins 5mg (if vitals are stable)
  10. Pedi-Dose:
    Not indicated
  11. Max Dose:
    Adult 15 mg
  12. Routes of Administration
  13. How Supplied
    5mg vials
Card Set
Metoprolol (Lopressor)
Paramedic Drugs