Question

A health care professional is caring for a patient who is receiving nitroglycerin (Nitrostat) IV and is changing to the oral form of the drug. The health care professional should recognize that the oral dose will be higher than the IV dose because of which of the following?

A. The IV dose crossing the blood-brain barrier
B. Decreased bioavailability because of the first-pass effect.
C. decreased half-life of the oral dose
D. increased rate of excretion of the oral dose.

Answer 1

The oral dose of nitroglycerin will be higher than the IV dose primarily because of decreased bioavailability due to the first-pass effect, where the liver metabolizes the drug before it reaches systemic circulation.

Step-by-step explanation:

The health care professional should recognize that the oral dose of nitroglycerin will be higher than the IV dose because of decreased bioavailability due to the first-pass effect. When a drug is administered orally, it first travels through the digestive system and the liver before reaching the systemic circulation. The liver can metabolize a significant portion of the drug before it enters the bloodstream, which reduces its concentration and necessitates a higher dose to achieve the intended pharmacological effect. In contrast, intravenous (IV) administration delivers the drug directly into the bloodstream, bypassing the first-pass metabolism, which results in a more immediate and higher plasma concentration of the drug.