Competency 1

Question 1

Pharmacodynamics

Answer 1

Pharmacodynamics is the study of the way drugs affect the body.

Question 2

Dose response

Answer 2

Dose response is the relationship between the minimal versus the maximal amount of drug dose needed to produce the desired drug response.

• Some patients respond to a lower drug dose
• others need a high drug dose to get desired response.

Question 3

Maximal efficacy

Answer 3

• max drug effect
• Ex. morphine and tramadol hydrochloride (Ultram) are prescribed to relieve pain.
• The maximum efficacy of morphine is greater than tramadol hydrochloride, regardless of how much tramadol hydrochloride is given.
• The pain relief with the use of tramadol hydrochloride is not as great as it is with morphine.

Question 4

Onset of action

Answer 4

Onset of action is the time it takes to reach the minimum effective concentration (MEC) after a drug is administered.

Question 5

Peak action

Answer 5

Peak action occurs when the drug reaches its highest blood or plasma concentration.

Question 6

Duration of action

Answer 6

Duration of action is the length of time the drug has a pharmacologic effect.

Question 7

Minimum effective concentration

Answer 7

the threshold level of a drug in plasma below which the efficiency of the drug as a treatment drops off sharply.

Question 8

Drug interaction

Answer 8

A drug interaction is defined as an altered or modified action or effect of a drug as a result of interaction with one or multiple drugs.

Question 9

Adverse drug reaction

Answer 9

An adverse drug reaction is an undesirable drug effect that ranges from mild untoward effects to severe toxic effects, including hypersensitivity reaction and anaphylaxis

Question 10

Drug incompatibility

Answer 10

Drug incompatibility is a chemical or physical reaction that occurs among two or more drugs in vitro. In other words, the reaction occurs between two or more drugs within a syringe, IV bag, or other artificial environment outside of the body.

Question 11

Drug-induced photosensitivity

Answer 11

A drug-induced photosensitivity reaction is a skin reaction caused by exposure to sunlight.

• caused by the interaction of a drug and exposure to ultraviolet A (UVA) light, which can cause cellular damage.
• two types:photoallergy and phototoxicity.

Question 12

Enzyme inducers

Answer 12

• drugs that promote induction of enzymes, by binding to it or activating
• produce cascade effect of drug function
• ex. Barbiturates like phenobarbital

Question 13

Enzyme inhibitors

Answer 13

Ex . Anitulcer drug cimetidine ( Tagamet) , decreases metabolism of certain drugs like theophylline, causing increase plasma concentration of theophylline

Question 14

Receptor theory

Answer 14

Drugs act through receptors by binding to the receptor to produce (initiate) a response or to block (prevent) a response. The activity of many drugs is determined by the ability of the drug to bind to a specific receptor. The better the drug fits at the receptor site, the more biologically active the drug is. It is similar to the fit of the right key in a lock.

Question 15

Agonist

Answer 15

Drugs that produce a response

Question 16

Antagonist

Answer 16

drugs that block a response

Question 17

Nonspecific drug effects

Answer 17

Drugs that affect various sites are nonspecific drugs and have properties of nonspecificity.
-effects may be either desirable or harmful. Drugs that evoke a variety of responses throughout the body have a nonspecific response.

Question 18

Nonselective drug effects

Answer 18

Drugs that affect various receptors are nonselective drugs or have properties of nonselectivity.
-Drugs that produce a response but do not act on a receptor may act by stimulating or inhibiting enzyme activity or hormone production

Question 19

Therapeutic index

Answer 19

• therapeutic index (TI) estimates the margin of safety of a drug through the use of a ratio that measures the effective (therapeutic) dose (ED) in 50% of people (ED50) and the lethal dose (LD) in 50% of people (LD50)
• The closer the ratio is to 1, the greater the danger of toxicity.

Question 20

Therapeutic drug range

Answer 20

The therapeutic range (therapeutic window) of a drug concentration in plasma is the level of drug between the minimum effective concentration in the plasma for obtaining desired drug action and the minimum toxic concentration (the toxic effect).

• includes both protein-bound and unbound portions of the drug
• If the therapeutic range is narrow, such as for digoxin (0.5 to 1 ng/mL), the plasma drug level should be monitored periodically to avoid drug toxicity.

Question 21

Protein bound drugs

Answer 21

As drugs are distributed in the plasma, many are bound to varying degrees (percentages) with protein (primarily albumin). Drugs that are greater than 89% bound to protein are known as highly protein-bound drugs

Question 22

Half-life

Answer 22

The half-life (1/2) of a drug is the time it takes for one half of the drug concentration to be eliminated.

Question 23

peak drug level

Answer 23

the highest plasma concentration of a drug at a specific time

Question 24

trough level

Answer 24

the lowest plasma concentration of a drug. The trough level measures the rate at which a drug is eliminated; levels are drawn immediately before the next dose of a drug is given.

Question 25

side effects

Answer 25

physiologic effects not related to desired drug effects

Question 26

drug toxicity

Answer 26

refers to how poisonous or harmful a substance can be. In the context of pharmacology, drug toxicity occurs when a person has accumulated too much of a drug in his bloodstream, leading to adverse effects within the body.Mar 7, 2016