Lecture 2

Question 1

Pharmacokinetics

Answer 1

study of movement of drugs throughout body
-ADME

Question 2

oral administration

Answer 2

safe, self-administered, economical, must be resistant to stomach enzmes and acid
-absoprtion affected by food intake, physcial activity
-harmful chemical processed by the liver

Question 3

Intravenous

Answer 3

most rapid and accurate, cannot be removed from body easily if overdosed or allergic

Question 4

Intramuscular

Answer 4

slower, more even absorption

Question 5

Rectal administration

Answer 5

may avoid first-pass liver metabolism, used for vominting or those unable to take oral medication, or infants

Question 6

Intraperitoneal

Answer 6

common for lab animals, injetion through abdominal wall into spce surrounding organs, used for cancer drugs

Question 7

Subcuteaneous

Answer 7

injection just below skin, slow and varibale absorption, can be slowed with oil or impant

Question 8

Inhalation

Answer 8

abosroption through lungs, rapid due to large surfae area

Question 9

Topical

Answer 9

applied to mucous membranes, local effect, could be absorbed into bloodstream

Question 10

Intranasal

Answer 10

Can pass blood-brain barrier, or for local effects in nasal passage

Question 11

Transdermal

Answer 11

through the skin using patches, controlled and sustained delivery of drug

Question 12

Epidural

Answer 12

spinal anesthetis to cerebrospinal fluid, pass blood-brain barrier

Question 13

Infusion pump

Answer 13

impant under skin of scalp, constant antibiotic dose into cerebral ventricles

Question 14

Gene therapy

Answer 14

application of DNA that encodes specific protein, used to increase or block gene expression to correct clinical condition, vectr needed to carry gene to cell nuclei, often viral vectors

Question 15

Absorption factors (3)

Answer 15

primarily dictated by rate of passage into blood stream of drug through cell membrane. Phospholipids of the membrne have a hydrophilic head and two hydrophobic tails in a bilayer. Only lipid soluble drugs can pass freely, others need receptor or channel or pores in capillaries
-also affected by rate stomach empties and size and sex of the person

Question 16

CSF

Answer 16

cerebralspinal fluid, fills subarachnoid space around brain and spinal cord. Many drugs cannot enter the CSF from the bloodstream

Question 17

Brain capillaries

Answer 17

have distinct morphology that limits movement of water soluble molecules

Question 18

blood brain barrier

Answer 18

separation between the brain capillaries and the brain/CSF

Question 19

Distribution

Answer 19

drug is distributed fastest to tissues with high blood flow and are vascular
slowe to low blood flow (muscle) and fat
slowest to tissues with lowest bloodflow (bone) and tendons

Question 20

Distribution depends on (3)

Answer 20

-cardiac blood flow
-degree of protein building
-volume of distribution
sometimes biological barriers such as blood brain barrier

Question 21

Drug transport

Answer 21

transporter proteins on cell membrane mediate drug concentrations in cells, uptake or efflux

Question 22

efflux transporters

Answer 22

remove drug from inside the cell, critical determinant of drug conentration inside cell, source of multii drug resistance

Question 23

uptake transporters

Answer 23

bring drugs into cell, critical determinant of drug concentration inside cell

Question 24

Drug depots

Answer 24

binding at inactive sites where no biological effect is initiated
-plasma proteins, fat, muscle
-cannot reach active sites or metabolism by liver
-reversible
-affects magnitude and duration of drug action -delays effects
-people vary in amount of depot binding
-nonselective, can bind different drugs
-can cause overdose, or higher expected blood levels of drug
-drugs reamin detectable in body for long times

Question 25

three routes of clearing drug from body

Answer 25

-hepatic metabolism -bile -urine

Question 26

drug metabolism

Answer 26

process of turning drug into its metabolites -increase water solubility and prepare for elimination -takes place in liver, minor metabolism in kidney, brain, skin and lungs

Question 27

Cytochrome p (CYP) 450

Answer 27

major role in drug metabolism variable acitivity between people cause of many drug drug interactions different types of CYP 450

Question 28

CYP 3A4

Answer 28

most abundant p450, metabolism of about half of drugs on the market

Question 29

CYP 450 induction and inhibition

Answer 29

drugs can induce or inhibit CYP enzymes, increasing or decreasing metabolism

Question 30

drug activation

Answer 30

sometimes metabolism actives a drug (prodrug) biotransformation into active compound

Question 31

kidneys

Answer 31

elimnation of drugs from blood into urine, pH of urine affects reabosrtion into kidney, also removes waste and excess salts from blood

Question 32

other routes of elimination

Answer 32

faeces, bile into faeces, lungs in air, breast milk, sweat

Question 33

Clearance (Cl)

Answer 33

total body clearance is sum of clearance from various metabolism pathways

Question 34

Pharmacodynamics

Answer 34

study of physiological and biochemical interaction of drug molecules with cell receptors in target tissue

Question 35

Neuropharmacology

Answer 35

drugs act on neurotransmitter receptors to enhance or reduce normal functioning of cell

Question 36

hormones

Answer 36

most hormones act on brain by binding receptors in cytoplasm or nucleus. alters cell function by triggering changes in gene expression

Question 37

receptor agonist

Answer 37

highest affinity for receptor and produce significant biologicl effect

Question 38

receptor antagonist

Answer 38

fits receptors but produces no cellular effect partial agonists hgave intermediate efficacy (partially bind receptor) inverse agonsis initiate biological affect that is opposite to agonist

Question 39

dose-response curve

Answer 39

describe extent of effect produced by given drug concentration

Question 40

threshold dose

Answer 40

smallest dose that exhibits measurable effect

Question 41

ED50

Answer 41

dose that produces half the maximal effect (50% effective dose) -tell you about potency of a drug

Question 42

maximum response

Answer 42

assume all receptors are bound to drug (ED100)

Question 43

drug tolerance

Answer 43

diminished response to drug after repeated exposure -increasing dosage needed to see same magnitude of biologial effect cross tolerance: tolerance to one drug an diminish effectiveness of other drugs

Question 44

pharmacogenetics

Answer 44

study of genetic basis of variability in drug response amoung individuals -goal: genetics that affect side effects and predict therpeutic response -i.e. differences in p450 enzyme genes, recpetors, transporters, signalling cascade proteins -some people may require different doses