Pharmacokinetics Overview
32 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the first phase of drug action responsible for the breakdown of drugs into smaller parts?

  • Disintegration Phase
  • Pharmacokinetic Phase
  • Pharmaceutic Phase (correct)
  • Pharmacodynamic Phase

    • During which phase do drugs need to be in solution to be absorbed by the body?

  • Pharmacodynamic Phase
  • Metabolic Phase
  • Pharmacokinetic Phase
  • Pharmaceutic Phase (correct)

    • Which process describes the time it takes for a drug to disintegrate and dissolve for absorption?

  • Absorption Rate
  • Elimination Rate
  • Metabolism Rate
  • Dissolution Rate (correct)

    • What is the second phase of the Pharmaceutic Phase that involves breaking down the drug into even smaller particles?

    <p>Dissolution</p> Signup and view all the answers

    Which phase follows the Pharmaceutic Phase in the drug action process?

    <p>Pharmacokinetic Phase</p> Signup and view all the answers

    Which factor increases drug absorption in acidic media?

    <p>Lower gastric pH levels</p> Signup and view all the answers

    What is the main concern with enteric coated drugs?

    <p>They should not be crushed before administration.</p> Signup and view all the answers

    How does the presence of food affect the dissolution and absorption of drugs?

    <p>It can interfere with the dissolution and absorption.</p> Signup and view all the answers

    What does bioavailability refer to in pharmacodynamics?

    <p>The availability of drug to the general circulation.</p> Signup and view all the answers

    At what pH range does normal gastric acid operate?

    <p>1.5-3.5</p> Signup and view all the answers

    What is the main characteristic of facilitated diffusion?

    <p>It requires a carrier such as an enzyme or protein.</p> Signup and view all the answers

    Which transport mechanism involves the engulfing of drug particles by cells?

    <p>Pinocytosis</p> Signup and view all the answers

    What role do transporters play in drug distribution in the body?

    <p>They can exclude drugs from certain body parts like the brain.</p> Signup and view all the answers

    What effect does protein binding have on a drug's tissue penetration?

    <p>Minimally protein-bound agents penetrate tissues better.</p> Signup and view all the answers

    Which statement accurately describes active transport?

    <p>It requires energy to move drugs against a concentration gradient.</p> Signup and view all the answers

    What is the primary purpose of excipients in drug formulations?

    <p>To assist in drug processing and stability</p> Signup and view all the answers

    Which of the following factors primarily affects the rate of drug dissolution?

    <p>The form of the drug (liquid vs. solid)</p> Signup and view all the answers

    In which phase of drug action is the effectiveness and stability of the delivery system maintained?

    <p>Pharmaceutic phase</p> Signup and view all the answers

    What is a key difference between liquid and solid drugs in terms of absorption?

    <p>Liquids are already in solution, allowing faster absorption</p> Signup and view all the answers

    Which phase of drug action involves the actual therapeutic effects of the drug?

    <p>Pharmacodynamic phase</p> Signup and view all the answers

    What role do excipients play in the identification of drug products?

    <p>Excipients aid in characterizing the drug's properties</p> Signup and view all the answers

    How do fillers in tablets affect drug formulation?

    <p>They allow the drug to take on a specific size and shape</p> Signup and view all the answers

    What aspect of gastric pH is important for drug dissolution?

    <p>Acidic pH increases dissolution of solid drugs</p> Signup and view all the answers

    What is the effect of lipid solubility on the absorption of a drug?

    <p>Lipid soluble drugs are absorbed faster than water-soluble drugs.</p> Signup and view all the answers

    Which factor contributes significantly to the rate of drug absorption?

    <p>Time of arrival and contact time at the absorption site.</p> Signup and view all the answers

    How does the degree of ionization affect drug absorption?

    <p>Non-ionized drugs can penetrate semipermeable membranes more easily.</p> Signup and view all the answers

    What is the relationship between chemical stability and drug absorption?

    <p>Higher chemical stability often correlates with slower absorption.</p> Signup and view all the answers

    What role does blood flow to the absorbing site play in drug absorption?

    <p>Increased blood flow generally enhances the absorption rate.</p> Signup and view all the answers

    Which of the following statements about drug solubility is correct?

    <p>Water-soluble drugs are absorbed faster and stay in circulation longer.</p> Signup and view all the answers

    What is meant by the lipid to water partition coefficient in drug absorption?

    <p>It indicates the solubility of a drug in both lipid and aqueous environments.</p> Signup and view all the answers

    Which statement is true regarding passive transport mechanisms for drug absorption?

    <p>Diffusion occurs in both aqueous and lipid environments.</p> Signup and view all the answers

    What is the impact of drug particle size on absorption?

    <p>Smaller particles are generally absorbed faster than larger particles.</p> Signup and view all the answers

    Study Notes

    Introduction to Pharmacokinetics

    • Pharmacokinetics involves drug movement and processing within the body.
    • Understanding encompasses three main phases: Pharmaceutic, Pharmacokinetic, and Pharmacodynamic.

    Pharmaceutic Phase

    • First phase where drug disintegration occurs in the gastrointestinal (GI) tract.
    • Necessary for the drug to be in solution for absorption.
    • Two key processes:
      • Disintegration: Breakdown of the drug into smaller particles.
      • Dissolution: Further breakdown into a liquid form for faster absorption.
    • Tablets comprise not just drugs but also excipients (fillers and inert substances) to:
      • Ensure proper size and shape.
      • Enhance dissolution and stability.

    Factors Affecting Dissolution Rate in the Pharmaceutic Phase

    • Form of drug: Liquid forms are absorbed more rapidly than solids.
    • Gastric pH: Acidic environments enhance disintegration; normal pH ranges from 1.5 to 3.5.
    • Age: Young children and elderly individuals have increased pH, potentially reducing absorption.
    • Enteric-coated drugs only disintegrate in alkaline environments, suitable for intestinal absorption.
    • Food presence can interfere with dissolution or enhance absorption.

    Pharmacokinetic Phase

    • Involves absorption into the bloodstream post-administration.
    • Majority (80%) of drugs are administered enterally (by mouth).
    • Key components influencing bioavailability:
      • Blood flow to absorption sites.
      • Surface area available for absorption.
      • Drug solubility: Water-soluble drugs are absorbed slower but stay longer in circulation; fat-soluble drugs are absorbed more quickly into fatty tissues.
      • Chemical stability and degree of ionization impact absorption rates.

    Mechanisms of Drug Transportation

    • Passive Transport:

      • Diffusion: Movement across cell membranes from high to low concentration.
      • Facilitated Diffusion: Requires a carrier protein, not energy-dependent, allows for rapid penetration of low lipid-solubility molecules like glucose.

    • Pinocytosis:

      • Engulfing of drug particles by cells through vesicles.

    • Active Transport:

      • Requires energy to move drugs against concentration gradients, often at specific sites in the small intestine.

    Distribution of Drugs

    • Refers to the process where drugs move from circulation to tissues.
    • Transporters are vital for crossing biological barriers; many drugs target transporters.
    • Key factors affecting distribution include:
      • Size of the organ and tissue.
      • Protein binding affinity: Minimally bound drugs penetrate tissues better but are excreted faster than highly bound counterparts.

    Summary

    • Pharmacokinetics consists of multiple phases that define how a drug behaves once administered.
    • Understanding these processes is critical for effective drug therapy and patient management in nursing and medical practice.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    This quiz covers the fundamental concepts of pharmacokinetics and its three phases: pharmaceutic, pharmacokinetic, and pharmacodynamic. Participants will learn how drugs interact with the body and the processes they undergo once administered. Enhance your understanding of drug action and its implications in nursing practice.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser