Intro to Pharmacology

Question 1

What are the three general drug mechanisms?

Answer 1

• deficiency (of some essential component - replacement therapy)
• excess action (of some normal or even essential ingredient - chemical antagonist, modified antibodies or exogenous substances)
• physiochemical environment (of the specific part of the body may be altered by a drug - “nonspecific”)

Question 2

In order for drugs to interact (“bind”) with receptors, they should have what four affinity characteristics?

Answer 2

• shape
• size
• charge
• atomic composition

Question 3

A drug must also have the necessary properties to be transported from its site of administration to its site of action. What are the five processes (drug dispositoin) that examine the properties of chemicals and characteristics of biologic process that influence tissue concentration of drugs and toxins?

Answer 3

• Kinetics
• Absorption
• Distribution
• Metabolism
• Excretion

Question 4

Where do most drugs act?

Answer 4

at receptors (for which they must have the affinity for)

Question 5

What is the therapeutic window?

Answer 5

a relative measure of dose that a drug can achieve a therapeutic effect without producing a side effect, calculated as the ratio of the TD50 (toxic dose) to the ED50 (effective dose) for the desired effect

Therapeutic window = TD50/ED50

Question 6

What does a therapeutic window of less than one suggest?

Answer 6

the drug will have side effects and could produce toxicity in patients at doses that are needed to produce the therapeutic effect

Question 7

What are three properties of drugs that favor passage across body membranes?

Answer 7

• low degree of ionization at physiologic pH
• low protein binding
• high lipid solubility

*most drugs cross by passive diffusion, but some need carrier-mediated transport (including active transport)

Question 8

Renal function is diminished in newborns, neonates, infants, and the elderly. The use of drugs eliminated primarily by the kidney in these patients may require _____ dosage adjustment.

Answer 8

downward

Question 9

Pharmacodynamics is defined by:
a - how the body deals with a drug
b - how the drug affects the body
c - deals with the adverse effects of a drug
d - is strictly the use of drugs in the treatment of disease

Answer 9

b - how the drug affects the body

Question 10

One can describe drugs as:
a - having only one effect
b - having only one effect within a therapeutic window
c - creating physiological processes to prevent disease
d - modifying physiological processes to treat disease

Answer 10

d - modifying physiological processes to treat disease