Pharmacokinetics II metabolism, excretion & lifespan changes Flashcards
What is First Pass metabolism?
First Pass metabolism refers to the process by which the concentration of a drug is significantly reduced before it reaches systemic circulation.
True or False: First Pass metabolism occurs in the liver.
True
Fill in the blank: The primary organ involved in First Pass metabolism is the _____ .
liver
What is the primary purpose of First Pass metabolism?
The primary purpose is to metabolize and eliminate drugs before they enter the bloodstream.
Which route of drug administration is most affected by First Pass metabolism?
Oral administration
Multiple Choice: Which of the following drugs undergoes extensive First Pass metabolism? A) Aspirin B) Nitroglycerin C) Morphine D) Insulin
A) Aspirin
What is the effect of First Pass metabolism on drug bioavailability?
First Pass metabolism usually decreases drug bioavailability.
True or False: First Pass metabolism can lead to the formation of active metabolites.
True
Fill in the blank: First Pass metabolism primarily occurs in the _____ and _____ .
liver; intestines
What is the first site of drug absorption for orally administered drugs?
The gastrointestinal tract
Multiple Choice: Which phase of drug metabolism is primarily involved in First Pass metabolism? A) Phase I B) Phase II C) Both A and B D) None of the above
C) Both A and B
What is the term for the percentage of a drug that reaches systemic circulation after First Pass metabolism?
Bioavailability
True or False: First Pass metabolism is a crucial mechanism for drug detoxification.
True
Fill in the blank: The _____ enzyme system is primarily responsible for Phase I reactions in First Pass metabolism.
Cytochrome P450
What type of drugs are more likely to undergo significant First Pass metabolism?
Lipid-soluble drugs
Multiple Choice: Which factor does NOT affect First Pass metabolism? A) Age B) Liver function C) Drug formulation D) Route of elimination
D) Route of elimination
What can be a consequence of high First Pass metabolism on drug dosing?
Higher doses may be required to achieve therapeutic effects.
True or False: First Pass metabolism can vary significantly among individuals.
True
Fill in the blank: First Pass metabolism can be influenced by factors such as _____ , _____ , and _____ .
genetics; diet; concurrent medications
What is the role of the portal vein in First Pass metabolism?
The portal vein transports absorbed drugs from the gastrointestinal tract to the liver.
Multiple Choice: Which of the following can be a strategy to bypass First Pass metabolism? A) Sublingual administration B) Oral administration C) Rectal administration D) All of the above
A) Sublingual administration
What is the impact of First Pass metabolism on drug half-life?
It can shorten the effective half-life of a drug.
True or False: First Pass metabolism can result in complete drug elimination before reaching systemic circulation.
False
Fill in the blank: In some cases, First Pass metabolism can activate a prodrug into its _____ form.
active