Pharmacology and Medication Administration Flashcards

A 70-kg patient requires a dopamine infusion at 5 mcg/kg/min. The solution is 400 mg in 250 mL D5W. What is the correct infusion rate in mL/hr?

Answer: 13.1 mL/hr

Concentration = 1,600 mcg/mL; dose = 350 mcg/min; rate = 350/1,600 = 0.219 mL/min × 60 = 13.1 mL/hr.

Naloxone reverses opioid toxicity by acting as a:

Answer: Competitive antagonist at opioid receptors

Naloxone is a competitive antagonist that displaces opioids from mu, kappa, and delta receptors to reverse toxicity.

Which condition is an absolute contraindication to nitroglycerin administration?

Answer: Inferior MI with right ventricular involvement

RV infarction relies on preload; nitroglycerin-induced vasodilation can cause profound hypotension in these patients.

A patient with suspected organophosphate poisoning is salivating, has bronchospasm, and bradycardia. Which drug is the antidote?

Answer: Atropine

Atropine competitively blocks muscarinic receptors, reversing the excessive cholinergic stimulation caused by organophosphates.

What is the half-life significance in pharmacology?

Answer: Time for plasma drug concentration to decrease by 50%

Half-life is the time required for the plasma concentration of a drug to be reduced by one-half.

A paramedic is preparing to administer 250 mg of a drug from a vial labeled 500 mg/10 mL. How many mL should be drawn up?

Answer: 5 mL

Concentration = 50 mg/mL; desired dose 250 mg ÷ 50 mg/mL = 5 mL.

Which beta-blocker is cardioselective and primarily blocks beta-1 receptors at therapeutic doses?

Answer: Metoprolol

Metoprolol is a cardioselective beta-1 blocker, reducing cardiac output and heart rate with less bronchospasm risk than nonselective agents.