Week 2 Pharmacokinetics

Question 1

What is pharmacokinetics

Answer 1

Study of what the body does to the drugs

Question 2

What is pharmacodynamics

Answer 2

Study of what the drugs do to the body

Question 3

What are the steps in a drugs journal through the body

Answer 3

Absorbtion, distribution, metabolism then excretion

Question 4

During absorption where does the drug enter

Answer 4

Plasma

Question 5

During distribution where does the drug leave to go to

Answer 5

Leaves the bloodstream and distribute into the interstitial and intracellular fluid

Question 6

What part of the body metabolizes

Answer 6

Kidney and liver

Question 7

Water soluble drugs penetrate the cell membrane through?

Answer 7

Aqueous channels or pores

Question 8

What is the function of the carrier protein

Answer 8

Facilitate the passage of large molecules

Question 9

What is facilitated diffusion

Answer 9

Movement of a molecule from a region on higher concentration to a lower concentration with the help of a transport molecule

Question 10

What is active transport

Answer 10

Movement from a region on low drug conc to the one of higher conc

Question 11

What is endocytosis

Answer 11

This involves engulfment of the drug molecule by the cell membrane and transport into the cell by pinching off the drug filled vesicles

Question 12

Exocytosis

Answer 12

This is used by cells to secrete many substances by a similar vesicle formation process

Question 13

Why can uncharged substance be passed easily

Answer 13

Because of it’s lipid solubility

Question 14

What is bioavailability

Answer 14

This is the fraction of the administered drugs that gain access to the systemic circulation

Question 15

What are the factors influencing bioavailability

Answer 15

First pass hepatic metabolism
Solubility of the drug
Chemical instability
Nature of the drug formulation

Question 16

What part of the body is the first pass hepatic metabolism usually associated with

Answer 16

Liver

Question 17

When is a drug bio equivalent

Answer 17

When two drugs show similar bioavailability and similar times to achieve peak blood conc

Question 18

What is therapeutic equivalence

Answer 18

When two drugs show the same result(efficacy) and safety

Question 19

What kind of plasma does acidic drug bind to

Answer 19

Albumin

Question 20

What kind of drugs does basic drugs bind to

Answer 20

Lipoproteins and alpha-1 glycoprotein

Question 21

Drugs are mostly eliminated by ?

Answer 21

Biotransformation and excretion

Question 22

Metabolism does what

Answer 22

Transforms lipophilic drugs into more polar excretable drugs

Question 23

What part of the body does biotransformation take place

Answer 23

Kidney and intestines

Question 24

Phase 1 metabolism consist of

Answer 24

Reduction
Oxidation
Hydrolysis reaction

Question 25

Drugs that must be metabolized to thier active form are what?

Answer 25

Prodrugs

Question 26

The phase 1 reaction of metabolism is catalyzed by ?

Answer 26

The cytochrome p450 system

Question 27

Another name for cytochrome p450 system

Answer 27

Microsomal mixed function oxidase

Question 28

Function of p450 system

Answer 28

Metabolise endogenous drugs and biotransform exogenous substance

Question 29

The most important route for elimination of drug is where?

Answer 29

Kidney

Question 30

Renal elimination of a drug

Answer 30

Glomerular filtration, proximal tubular secretion and distal tubular reabsorption

Question 31

What elimination kinetic do most drugs in clinical use demonstrate

Answer 31

First order kinetics

Question 32

In first order kinetics the rate of elimination of drug is proportional to what

Answer 32

The drug concentration

Question 33

What drug shows zero order elimination

Answer 33

Ethanol

Question 34

At high toxic concentration what drug shows zero order elimination

Answer 34

Phenytoin and aspirin

Question 35

Active transport is driven by what

Answer 35

Hydrolysis of atp

Question 36

Which drug is transported through endocytosis

Answer 36

Vitamin b12

Question 37

Which neurotransmitter is secreted by exocytosis

Answer 37

Norepinephrine

Question 38

other places where the firt pass metabolism can occur

Answer 38

Lungs, gastrointestinal tract and vasculature

Question 39

Drug distribution depends on?

Answer 39

Blood flow Capillary permeability Degree of binding of the drug to plasma and tissue proteins Hydrophobicity of the drug

Question 40

Function of phase 1 metabolism

Answer 40

Convert lipophilic molecules into more polar molecules by introducing a polar functional group like OH or NH2

Question 41

Drugs that increase the synthesis of one or more cyp isozymes are

Answer 41

Phenobarbital, rifampin and carbamazepine