Routes, Doses, Onset, Duration, Peak, and Half-life of Various Analgesics
Routes, Doses, Onset, Duration, Peak, and Half-life of Various Analgesics ( 5 Questions)
A nurse is reviewing the pharmacokinetics of different routes of administration for analgesics with a nursing student.
The nurse asks the student, “Which route has the fastest onset and peak of action?” What is the correct answer by the student?
The oral route is wrong because the oral route involves swallowing the drug, which then passes through the stomach and intestines before reaching the bloodstream. This route has a slower onset and peak of action due to factors such as gastric emptying time, food intake, and first-pass metabolism.
The rectal route is wrong because the rectal route involves inserting the drug into the rectum, where it is absorbed by the rectal mucosa and enters the systemic circulation. This route has a similar onset and peak of action to the oral route but may have better absorption and less first-pass metabolism.
This is because the intravenous route delivers the drug directly into the bloodstream, bypassing the first-pass metabolism in the liver and the absorption barriers in the gastrointestinal tract. This results in a faster onset and peak of action compared to other routes.
The intramuscular route is wrong because the intramuscular route involves injecting the drug into a muscle, where it is absorbed by the capillaries and enters the bloodstream. This route has a slower onset and peak of action than the intravenous route, but faster than the oral and rectal routes. The rate of absorption depends on factors such as blood flow, muscle mass, and injection site.
This is because the intravenous route delivers the drug directly into the bloodstream, bypassing the first-pass metabolism in the liver and the absorption barriers in the gastrointestinal tract. This results in a faster onset and peak of action compared to other routes.
Choice A. Oral route is wrong because the oral route involves swallowing the drug, which then passes through the stomach and intestines before reaching the bloodstream. This route has a slower onset and peak of action due to factors such as gastric emptying time, food intake, and first-pass metabolism.
Choice B. Rectal route is wrong because the rectal route involves inserting the drug into the rectum, where it is absorbed by the rectal mucosa and enters the systemic circulation. This route has a similar onset and peak of action to the oral route but may have better absorption and less first-pass metabolism.
Choice D. Intramuscular route is wrong because the intramuscular route involves injecting the drug into a muscle, where it is absorbed by the capillaries and enters the bloodstream. This route has a slower onset and peak of action than the intravenous route, but faster than the oral and rectal routes. The rate of absorption depends on factors such as blood flow, muscle mass, and injection site.