Module 1: Part 3 Flashcards
What is pharmacokinetics?
Pharmacokinetics is the study of how drugs are absorbed, distributed, metabolized, and excreted in the body.
What is the primary process by which drugs enter the bloodstream?
Absorption.
True or False: Distribution refers to how a drug is spread throughout the body after absorption.
True.
Fill in the blank: The four main processes of pharmacokinetics are absorption, distribution, __________, and excretion.
metabolism.
What does metabolism refer to in pharmacokinetics?
Metabolism refers to the chemical processes that convert a drug into its active or inactive forms in the body.
Which organ is primarily responsible for drug metabolism?
The liver.
Multiple Choice: Which of the following is NOT a phase of pharmacokinetics? A) Distribution B) Excretion C) Elimination D) Absorption
C) Elimination.
What is excretion in the context of pharmacokinetics?
Excretion is the process by which drugs and their metabolites are eliminated from the body, primarily through kidneys (urine), hepatobilliary system (bile into intestines where reabsorbed or in feces).
Also excreted through lungs (volatile/gaseous anaesthetics), sweat, saliva, tears and breast milk.
True or False: The rate of absorption can affect the overall efficacy of a drug.
True.
Short Answer: Name two factors that can influence drug absorption.
pH of the environment and presence of food in the stomach.
What is the term for the fraction of an administered dose of a drug that reaches systemic circulation?
Bioavailability.
Multiple Choice: Which of the following routes of administration typically has the highest bioavailability? A) Oral B) Intravenous C) Intramuscular D) Subcutaneous
B) Intravenous.
Fill in the blank: The volume of distribution is a measure of how extensively a drug __________ throughout the body.
distributes.
What is the significance of half-life in pharmacokinetics?
Half-life is the time it takes for the concentration of a drug in the bloodstream to reduce by half, influencing dosing schedules.
True or False: Drugs that are highly protein-bound have a larger volume of distribution.
False.
Short Answer: What role do enzymes play in drug metabolism?
Enzymes facilitate the chemical reactions that transform drugs into their metabolites.
What is the first-pass effect?
The first-pass effect is the metabolism of a drug by enzymes in the gut wall and liver before it reaches systemic circulation.
Multiple Choice: Which of the following can affect drug excretion? A) Kidney function B) Liver function C) Age D) All of the above
D) All of the above.
Fill in the blank: The process of __________ is critical for the elimination of water-soluble drugs from the body.
excretion.
Which of the following factors can influence drug delivery across the blood-brain barrier? A) Lipophilicity B) Molecular size C) Charge D) All of the above
D) All of the above
Short Answer: How does the blood-brain barrier impact pharmacokinetics?
It affects the absorption, distribution, metabolism, and excretion of drugs in the central nervous system.
What is ‘steady-state’ in pharmacokinetics?
When the amount of drug entering the body = the amount of drug leaving the body. Maintained in the bloodstream through repeated regular-interval dosing.
