Question

A nurse educator is teaching a module on pharmacokinetics to a group of newly licensed nurses. Which of the following statements by a newly licensed nurse indicates an understanding of the 1st-pass effecct?

A. Some meds block normal receptor activity regulated by endogenous compounds or receptor activity caused by other meds.
B. Some meds may have to be administered by a nonenteral route to avoid inactivation as they travel through the liver.
C. Some meds leave the body more slowly & therefore have a greater risk of accumulation & toxicity.
D. Some meds have a wide safety margin, so there is no need for routine serum medication level monitoring.

Answer 1

The correct answer is B. The first-pass effect refers to the initial metabolism of a drug in the liver before it reaches systemic circulation. Some medications may have to be administered by a nonenteral route to avoid inactivation as they travel through the liver.The correct answer is: B

Step-by-step explanation:

The statement that indicates an understanding of the 1st-pass effect is option B: Some medications may have to be administered by a nonenteral route to avoid inactivation as they travel through the liver.

The first-pass effect refers to the initial metabolism of a drug in the liver before it reaches systemic circulation. When a medication is taken orally, it is absorbed through the gastrointestinal (GI) tract and enters the portal circulation, which carries it directly to the liver. In the liver, the drug is metabolized by enzymes before it reaches the general circulation.

This first-pass metabolism can greatly reduce the bioavailability of a drug, meaning that less of the medication reaches the systemic circulation to produce a therapeutic effect. For some medications, the first-pass effect can be so significant that their oral bioavailability is very low, and they may need to be administered through a nonenteral route (such as intravenous or intramuscular injection) to bypass the liver and avoid inactivation.

For example, nitroglycerin is a medication used to treat angina (chest pain). If taken orally, nitroglycerin undergoes extensive first-pass metabolism in the liver, leading to low bioavailability. Therefore, it is typically administered sublingually (under the tongue) or transdermally (through the skin) to bypass the liver and achieve a therapeutic effect.