Pharmacology, Pharmacokinetics

Question 1

Dose

Answer 1

Amount of drug given
Usually expressed in mg/kg
Measure of efficacy
See the minimally effective dose
Important in drug safety

Question 2

Dosage

Answer 2

Administration of drug per unit of time

Question 3

Pharmacodynamics

Answer 3

The action of drugs and their mechanism of action

Question 4

Affinity

Answer 4

Ability to bind to the receptor

Question 5

Efficacy

Answer 5

Degree of biological activity

Question 6

Agonist

Answer 6

Ligand that binds to receptor to elicit a response

Question 7

Indirect Agonist

Answer 7

Molecule that does not bind directly to a receptor but increases the amount of exogenous ligand

Question 8

Partial Agonist

Answer 8

Agonist that has an intermediate activity at the receptor

Question 9

Antagonist-

Answer 9

Molecule that binds to receptor but has no intrinsic activity

Question 10

Inverse Agonist

Answer 10

Agonist that binds to the receptor but has the opposite effect

Question 11

Mixed agonist/antagonist

Answer 11

Acts as an agonist that blocks the effect of another agonist

Question 12

Potency

Answer 12

Amount of drug required to produce a specific effect of given intensity as compared to a standard reference
Considers both affinity and efficacy

Question 13

4 Principles of Pharmacokinetics

Answer 13

Absorption- Get drug into blood stream
Distribution- Get drug to target organ
Metabolism- Usually inactivates the drug, sometimes makes it more active
Excretion- Removes drug from Body

Question 14

Time Effect Curves

Answer 14

Provides documentation of how much drug enters the body per unit time
Profile- Gradual increase in levels until peak concentration and then a decrease over time
Many variable control this time profile

Question 15

Duration of Action

Answer 15

The amount of time spent in the therapeutic range

Question 16

Routes of Administration

Answer 16

Oral- easy but slow
Inhalation- Fastest
Injection
Topically- Slow and erratic
Buccal- gums and cheeks
Rectal- Generally Slow

Question 17

Determinants of Dissolution

Answer 17

Dissolution Rates
Gastric Emptying Rate
Intestinal Motility
Drug Interactions in Gut Lumen
Passage Through Gut Wall

Question 18

Dissolution Rates

Answer 18

Physiochemical properties
Crystal size and form
Special Formulation- sustained release

Question 19

Gastric Emptying Rate

Answer 19

Stability of drug at acid pH
Solution or solid
Presence of other food items: food, antacids, other drugs, disease of stomach

Question 20

Intestinal Motility

Answer 20

Dissolution of slowly soluble drugs

Chemical degradation or metabolism by microflora that live in the GI system

Question 21

Drug Interactions in Gut Lumen

Answer 21

Complexation
Adsorption
Food interactions

Question 22

Passage Through the Gut wall

Answer 22

-physiochemical characteristics of drug

Metabolism by enzymes in the intestinal endothelium

Question 23

Drug -Phillic

Answer 23

Lipophilic- Pass easily through gut wall, more easily absorbed
Hydrophillic- Easily dissolved in blood but harder to pass through gut wall

Question 24

Sustained Release Formulation

Answer 24

Drug levels more stable over time, fewer side effects, better medication compliance
Most offer once a day dosing, but some injections offer once a month

Question 25

Blood Level Monitoring

Answer 25

Gold Standard for detecting drugs and whether they are biologically active
5-10 ml sample is collected for analysis

Question 26

Blood Brain Barrier

Answer 26

Keeps large molecules out of the blood
Composed of specialized cells that alter the function of the capillaries
Block the junction between capillaries and cover the area with a glial sheath

Question 27

Metabolism

Answer 27

Process of breaking down a drug or food so it can be utilizes/eliminated
Generally, lipid soluble chemicals are broken down into water soluble chemicals

Question 28

Biotransformation

Answer 28

Preparation for elimination

Question 29

First Pass Effect

Answer 29

Extent to which the liver removes drug from blood as it is passing through the portal vein before entering systemic circulation

Question 30

Metabolism

Answer 30

Enzymes in the liver regulate metabolism
High amount of interindividual variation
Cytochrome P450 type is major enzyme
Small molecules --> kidney --> urine
Large molecule --> intestine --> feces

Question 31

Cytochrome P450

Answer 31

Enzyme located in hepatocytes

Diverse gene that metabolizes wide range of drugs and food

Question 32

Elimination

Answer 32

Primary Route through feces/urine

- Also through saliva, tears, breath and sweat

Question 33

Urine Screen Drug Test

Answer 33

Principal way to measure if someone has taken drugs
Low cost and relatively sensitive
- See active drugs or metabolites
- Gives no indication to amount or when taken

Question 34

Faking a Urine Screen

Answer 34

• Used at many work locations

Several products, including artificial urine and dispensing devices to help fake

Question 35

Non-Urine Drug Tests

Answer 35

Hair- 1 week to 3 mos
Oral- 1-2 days
Urine 3-5 days
Blood minutes to days

Question 36

Hair Drug Test

Answer 36

• Minute amounts of drug get trapped in hair cortex
• Tracks drug use over months
  Simple and non-invasive
  Results stand up in court
  CON
  Expensive
  Some tests can take 5 days
  Only a dozen drug classes can be used

Question 37

Placebo Response

Answer 37

Inert substance
response can be measured
Works best on symptoms and signs that oscillate throughout the illness
- More related with an expectancy or desire for the drug to work
-Placebo manipulations reduce neuronal activity in regions that are sensitive to pain
- Reductions in activity associates with perceived reduction in pain