Principles of Drug Action

Question 1

Pharmacokinetics

Answer 1

how drugs move in the body; process by which drugs are distributed in the body

Question 2

Pharmacodynamics

Answer 2

process by which drugs influence cell physiology

Question 3

Drug Action in Pharmacokinetics(4)

Answer 3

1. absorption
2. distribution
3. metabolism
4. excretion

Question 4

Phospholipid bilayer

Answer 4

made of hyrdocarbons and phosphates; must be lipid soluble to cross barrier

Question 5

Molecular Size

Answer 5

small compounds can go through channels or pores.

larger compound may not fit

Question 6

Solubility

Answer 6

the more lipid soluble a medication, the easier it can cross membranes

Question 7

Degree of Ionization

Answer 7

the more ionized, the less lipid soluble so can’t move across membranes

Question 8

Concentration

Answer 8

moves high to low

Question 9

Types of transport (3)

Answer 9

1. passive process
2. active process
3. facilitated transport

Question 10

Passive processes (2)

Answer 10

1. Diffusion- across whole membrane

2. Filtration- through channels

Question 11

Factors affecting diffusion (3)

Answer 11

1. concentration gradient (high to low)
2. lipid solubility
3. ionization

Question 12

Active transport ( 4 things to know)

Answer 12

1. requires energy, going from low to high (uphill) against concentration gradient.
2. Molecules too big or poorly lipid soluble can be carried across this way.
3. Is more rapid than diffusion.
4. Occurs across neuronal membranes, the choroid plexus, renal tubular cells, and hepatocytes

Question 13

Facilitated transport

Answer 13

needs carrier to facilitate in transport; cannot occur against electrochemical gradient; glucose and insulin

Question 14

Factors that affect absorption

Answer 14

1, drug solubility

2. pH
3. Concentration
4. circulation
5. surface area