Pharmacology Ch 6 For Nursing 205

Front 1

Pharmacodynamics

Back 1

p57 Medicine and change. It refers to how a medicine CHANGES the body. Branch of pharmacology that is concerned w/ the mechanisms of drug action and the relationship btwn drug conc. and responses in the body.

Front 2

Knowledge of what 3 things will help the nurse provide safe and effective treatment?

Back 2

p57 therapeutic indexes, dose-response relationships, and drug-receptor interactions

Front 3

Frequency distribution curve

Back 3

p57 Interclient variability in responses to drugs can best be understood by examining ________. It is a graphical representation of no. of clients responding to a drug action at different doses. Curve does not show magnitude of response, only whether a measurable response occurred w/in client.

Front 4

Median Effective Dose (ED 50)

Back 4

p58 Dose in the middle of the frequency distribution curve. Dose required to produce a sp. therapeutic response in 50% of a group of clients. Standard or average dose. Satisfactory response for only 50% of the population!

Front 5

Frequency distribution curve can also be used to represent ______
Median Lethal Dose

Back 5

The safety of a drug. Median Lethal Dose (LD 50) is often determined in preclinical trials, as part of drug development. LD 50 is the dose of drug that will be lethal in 50% of a group of animals.

Front 6

A drug's therapeutic index

Back 6

the ratio of a drug's LD 50 to its ED 50 (as a fraction). The larger the diff. btwn the 2 doses, the greater the therapeutic index. The therapeutic index is a measure of a drug's safety margin: the higher the value, the safer the medication.

Front 7

Median Toxicity Value

Back 7

p58. Because the LD 50 cannot be experimentally determined in humans, the ____ is a more practical value in a clinical setting. The TD 50 is the dose that will produce a given toxicity in 50% of a group of clients. (used in medications in populations)

Front 8

Graded dose-response relationship

Back 8

(used in individuals). 3 distinct phases. Phase 1 cocurs at the lowest doses. Few targeted cells have been affected by drug. Phase 2. straight line portion of curve - linear relationship btwn amount of drug administered and degree of response obtained fr client. Phase 3 plateau is reached in wh/ increasing the drug dose produces no additional therapeutic response.

Front 9

Phase 3 contd

Back 9

Explanations for plateau: 1. all receptors for drugs are occupied or 2. drug has brought 100% relief . In phase 3 increasing dose does not produce greater therapeutic results, it may produce adverse effects.

Front 10

Within a pharmacological class, not all drugs are equally effective at treating a disorder. Drugs in the same class are effective at different doses.

Back 10

Potency and Efficacy overview
(2 ways to compare medications w/in therapeutic and pharmacological classes)

Front 11

Potency

Back 11

p59 A drug that is more potent will produce a therapeutic effect at a lower dose, compared w/ another drug in the same class.

Front 12

Efficacy

Back 12

is the magnitude of maximal response that can be produced fr. a particular drug. Looking for the higher maximal response. Efficacy is almost always more important than potency.

Front 13

A cellular macro-molecule to which a medication binds to initiate its effects is called a ____.

Back 13

p60 receptor. Receptor theory explains the mechanism by wh/ MOST drugs produce their effect. Theses receptors do not exist in the body solely to bind drugs, but their normal fx is to bind endogenous molecules such as hormones, neurotransmitters, and growth factors.

Front 14

Although a drug receptor can be any type of macromolecule, the vast majority are _____.

Back 14

p60 Proteins. receptors - several protein subunits arranged around a central canal or channel.

Front 15

Once bound, drugs may trigger a series of __________ events w/in the cell.

Back 15

p61 Second messenger. IE conversion of ATP to cyclic AMP, release of intracellular calcium, or activation of sp G proteins and associated enzymes. These biochemical cascades initiate the drug's action by either stimulating or inhibiting a normal activity of the cell.

Front 16

2 other receptors that aren't bound to plasma membrane

Back 16

p61 intracellular molecules such as DNA or enzymes in the cytoplasm. By interacting w/ these, medications are able to inhibit protein synthesis or regulate events such as cell replication and metabolism. ex steroid med., vit, and hormones.

Front 17

subtypes

Back 17

not just all receptors, but A and B receptors, then A1 and A2, greater and greater sp. to a receptor. More and more receptor subtypes are being discovered. These permit "fine-tuning" in pharmacology. Avoiding unnecessary adverse effects.

Front 18

Non-specific cellular responses

Back 18

Drugs that act independently of cellular receptors. These are associated w/ other mechanisms, such as changing the permeability of cellular membranes, depressing membrane excitability, or altering the activity of cellular pumps. Ethyl alcohol

Front 19

Agonist

Back 19

a drug that produces the same type of response as the endogenous substance. Sometimes produce a greater maximal response than the endogenous chemical.

Front 20

Partial Agonist

Back 20

describes a medication that produces a weaker, or less efficacious response than an agonist.

Front 21

Antagonist

Back 21

p62 A drug that occupies a receptor and prevents the endogenous chemical from acting. Antagonists often compete w/ agonists for the receptor binding sites.

Front 22

Functional antagonists

Back 22

(not all antagonism is associated with receptors) The _____ inhibit the effects of an agonist not by competing for a receptor but by changing pharmacokinetic factors. Antagonists can slow absorption of a drug or speed metabolism of a drug.

Front 23

Human Genome Project

Back 23

p62 may allow for drugs to be customized for clients w/ similar genetic characteristics. Performing a DNA test will prevent idiosyncratic responses.

Front 24

Idiosyncratic responses

Back 24

unpredictable and unexplained drug reactions were called _____.

Front 25

Pharmacogenetics

Back 25

area of pharmacology that examines the role of hereditary in drug response. ie the identification of subtle genetic diff. in drug-metabolizing enzymes.