Module 1 ADME

Question 1

absorption

Answer 1

rate at which and extent to which a drug leaves its site of administration

Question 2

bioavailability

Answer 2

extent to which a drug reaches systemic circulation

- fraction absorbed

Question 3

concentration and absorption

Answer 3

higher concentration = greater absorption

Question 4

circulation and absorption

Answer 4

Enhance absorption
- inc. blood flow, local massage, heat application
Slow absorption
- dec. blood flow, vasoconstrictor agents, shock, other disease factors.

Question 5

drug solubility and absorption

Answer 5

how drug is dissolved

• extent of dissolution
• rate of dissolution

Question 6

enteral/oral advantages

Answer 6

safe
convenient
economical
painless
systemic infections less likely

Question 7

enteral/oral disadvantages

Answer 7

absorption challenges
- destruction in harsh GI environment 
- passage across GI tract epithelium: pH, pKa
- slow delivery
- first-pass metabolism 
nonionized, lipophilic drugs favored 
weak acids absorb in stomach
weak bases absorb in SI

Question 8

rectal advantages

Answer 8

when oral is not available
- vomiting, unconscious
~50% bypasses liver

Question 9

rectal disadvantages

Answer 9

erratic absorption

can cause irritation of rectal mucosa

Question 10

Parenteral advantages

Answer 10

IV, IM, SubQ, IA, IT
rapid delivery
high bioavailability
no first-pass
no harsh GI environment

Question 11

parenteral disadvantages

Answer 11

irreversible
administration technique
pain/fear
inc. risk of infection

Question 12

mucous membranes

Answer 12

sublingual 
ocular
pulmonary
nasal
rectal 
urinary
reproductive tract

Question 13

mucous membrane advantages

Answer 13

rapid delivery
no hepatic first pass
no harsh GI environment

Question 14

transdermal advantages

Answer 14

simple
convenient
painless
no hepatic first pass
no harsh GI environment
continuous administration

Question 15

transdermal disadvantages

Answer 15

requires drug with high lipophilicity
slow delivery
irritation

Question 16

distribution initial phase

Answer 16

drugs must reach target organs in therapeutic concentrations
initial phase: reflects blood flow
- delivery to muscle, most viscera, skin, and fat is slower

Question 17

distribution second phase

Answer 17

distribution to tissues 
- drug must be free to move into tissue
rapid distribution to: 
- interstitial compartment
restricted distribution
- lipid-insoluble drugs 
- drug-binding plasma proteins

Question 18

volume distribution (Vd) =

Answer 18

Vd = Dose/drug plasma

Question 19

low Vd

Answer 19

drug retained within vascular compartment

• highly bound to protein
• dec. excretion

Question 20

high Vd

Answer 20

highly distributed into non-vascular compartments

- cleared easier