Final definitions

Question 1

drug

Answer 1

a chemical agent used in the dx, tx or prevention of disease

Question 2

Drug routes

Answer 2

enteral, parenteral, inhalation, intranasal, intrathecal, topical, transdermal, sublingual, and IV

Question 3

What’s unique about sublingual route?

Answer 3

drug delivered to blood stream, skips first pass by liver

Question 4

What’s unique about IV route?

Answer 4

100% bioavailability

Question 5

Drug absorption rule

Answer 5

small non-ionized, lipid soluble drugs will more readily cross plasma membrane relative to larger, ionized and/or water soluble molecules

Question 6

bioavailability

Answer 6

is the fraction of administered drug that reaches the systemic circulation in an unchanged form. Solubility of agent, hepatic metabolism of agent, and chemical binders influence bioavailability.

Question 7

Half life

Answer 7

is the amount of time required for the plasma concentration of a drug to decrease by 50% after discontinuation of the drug.

Question 8

loading dose

Answer 8

initial dose of drug that is higher than subsequent doses for purpose of achieving therapeutic drug concentration.

Question 9

maintenance dose

Answer 9

dose of a drug that maintains a steady state plasma concentration in therapeutic range.

Question 10

onset

Answer 10

amount of time it take for a drug to exert effects

Question 11

Duration

Answer 11

the length of time for which a drug exerts therapeutic effects.

Question 12

Efficacy

Answer 12

refers to the degree to which a drug is able to induce maximal therapeutic effects. Efficacy is a term often used to compare drugs of different classes.

Question 13

Potency

Answer 13

is the amount of drug required to produce 50% of the maximal response that the drug is capable of producing. Potency is more frequently used to compare drugs of similar classes.

Question 14

EC50

Answer 14

: effective concentration 50 is the concentration of an agent which induces a specific clinical effect in 50% of subject to which drug has been administered.

Question 15

LD50

Answer 15

lethal dose 50 is the concentration of an agent which causes death in 50% of subject to which that agent has been administered.

Question 16

Therapeutic index: (TI)

Answer 16

(TI) = LD50/EC50. - A measure of drug’s safety. Large number is good, small number is bad.

Question 17

Agonist

Answer 17

an agent that can bind to a receptor site and elicit a defined therapeutic response

Question 18

partial agonist

Answer 18

occupies a binding site but causes less of response than a full agonist

Question 19

antagonist

Answer 19

inhibit or block response caused by agonist

Question 20

competitive antagonist

Answer 20

interact with receptors at the same site as agonist and thus compete for binding.

Question 21

non-competitive antagonist

Answer 21

bind to a site other than the agonist. (effects are generally irreversible)

Question 22

tolerance

Answer 22

a decreased response to a drug. Clinically dose of drug must be increased to achieve a similar effect of the drug at its original dose.

Question 23

supplement

Answer 23

intended to “supplement the diet”, contains vitamins, minerals, herbs or botanicals, or a concentrate/metabolite/constituent or combo of these things.

• May not claim to treat, diagnose, cure or prevent disease
• Can make “structure or function claims”….. can support joints…etc.

Question 24

pregnancy Rx classification

Answer 24

• A: controlled studies show no risk
• B: no evidence of risk in humans
• C: risk cannot be ruled out
• D: positive evidence of human fetal risk
• X: contraindicated in pregnancy
  o Most drugs are category C— so contraindicated w/ pregnancy.

Question 25

FDA/DEA classification Rx

Answer 25

CI: no approved medical use (LSD, heroine)
CII: high potential for abuse, increased rate of addiction, need a new script to refil.
CIII: moderate potential for abuse
CIV: low potential for abuse (lowest dose of codeine)
OTC: available over the counter.