How Drugs Work: The Nuts And Bolts Of Therapeutics

Question 1

What is pharmacodynamics

Answer 1

The study of biochemical and physiological effects of drugs on the body and the mechanims of drug action and the relationship between the drug concentration and effect

Question 2

In simple word what is pharmacodynamics

Answer 2

What the drug does to the body

Question 3

When a drug and its receptor come together what does this produce

Answer 3

An effect (d+r= dr)

Question 4

What are the 2 types of actions of a drug

Answer 4

Non specific action

Specific action

Question 5

Give an example of a non specifc action of a drug

Answer 5

Antacid which reacts with gastric acid to neutralise the gastric acid

Question 6

Give a specific action of a drug

Answer 6

Drugs that act on chemically sensitive protein e.g receptors or specific target molecules

Question 7

What are drug target examples

Answer 7

G protein coupled receptors
Kinase linked receptors
Dna linked receptors
Voltage dependent ion chanells
Enzymes
Transporter proteins

Question 8

What are g protein coupled receptors

Answer 8

Receptor binding that leads to interaction with g protein couples with intracellular enzyme activation (cAMP, cGMP) or ion channel

Question 9

What are kinase linked receptors

Answer 9

Receptor binding that activates intracellular protein kinase associated reactions

Question 10

Where are dna linked receptors located

Answer 10

In the cell nucleus

Question 11

What does activation of dna linked receptors activate or inhibit

Answer 11

Protein synthesis

Question 12

What happens when drugs target voltage dependent ion channels

Answer 12

Drugs alter the conductance of the ion channle and enable the cell to be excitable

Question 13

How do drugs target enzymes

Answer 13

Subtrate competetion or modify the enzyme

Question 14

What are transporter proteins

Answer 14

Special proteins that carry ions or molcules across the cell membranes

Question 15

What does drug receptor interaction depend on

Answer 15

Chemical composition such as polarity
Stereochemical disposition
Ability for drug to reach receptor binding zone

Question 16

As we increase the drug concentration what happens to the receptor concentration (ie concentration of occupied receptors)

Answer 16

Increases

Question 17

Eventually as the drug concentration continues to increase what happens to the proportion of receptors bound

Answer 17

Become 100% occupied

Question 18

What is affinity

Answer 18

The probabiltiy of the drug occupyin the receptor

Question 19

What can affinity be influenced by

Answer 19

Ageing
Genetic mutations
Other drugs

Question 20

What is selectivity

Answer 20

The degree which a drug acts on a given site compared to other sites

Question 21

What does efficacy mean

Answer 21

The ability of a drug receptor complex to produce a maximum functional response

Question 22

Give an example of efficacy

Answer 22

Drug A will have a greater efficacy than drug b no matter how much you increase the dose of drug b

Question 23

What is an agonist

Answer 23

A chemical that binds to receptors and activates it to produce a biological response

Question 24

What is an antagonist

Answer 24

A chemicla that bind and blocks agonist mediated responses rather than providing a biological response

Question 25

What is a natural agonist

Answer 25

Natural agonist in the body that work on natural receptors e.g dopamine that works in the brain

Question 26

What is a partial agonist

Answer 26

A chemical that binds to the receptor and has a partial efficacy compared to the full agonist

Question 27

What is potency

Answer 27

A measure of drug activity expressed in terms of the amount to produce an effect of given intensity

Question 28

What does a highly potent drug produce

Answer 28

A large response at a low concentration

Question 29

On a dose response curve what is the more potent drug going to be shifted to

Answer 29

To the left

Question 30

What is tolerance

Answer 30

With repeated doses the effect of a drug decreases

Question 31

What are the reasons for tolerance

Answer 31

Downregulation of receptor number Decreased receptor binding affinity Modulation downstream response to initial response

Question 32

What is a withdrawal reaction

Answer 32

When tolerance is present and the body is desensitised to the effect of the drug, so when the drus is withdrawan it causes a rebound effect/reaction.

Question 33

What is therapeutic efficacy

Answer 33

The effectiveness of a drug to produce an effect

Question 34

What is an ON target response

Answer 34

When we give a drug and want to act on on a particular receptor

Question 35

What is an OFF target response

Answer 35

When the drug affects other receptors that we do not want it to

Question 36

What is the therapeutic index

Answer 36

The ratio of the dose that produces toxicity to the dose that produces a clinically desired/ effective response

Question 37

What is a dose

Answer 37

The total quantity of an active agent taken at any one time

Question 38

Is dose and dosage the same

Answer 38

No because dosage considers the body weight or surface area

Question 39

What is formulation

Answer 39

Altering the form of a drug to make the medicine more effective and more acceptable to the patient

Question 40

What is pharmokinetics

Answer 40

What the body does to the drug

Question 41

What factors do we need to consider in pharmokinetics

Answer 41

Absorption Distribution Metabolism Elimination

Question 42

In formulation what do we need to consider

Answer 42

Route of administration

Question 43

What are the 3 types of route administration

Answer 43

1. Topical 2. Enteral 3. Parenteral

Question 44

What is topical adminstration

Answer 44

Applying the drug directly to where action is desired

Question 45

What is enteral administration

Answer 45

The desired effect is system i,e non local so the substance is given by the digestive tract

Question 46

What is parenteral adminstration

Answer 46

The desired effect is systemic i.e non local so the substance is given by other routes except the digestive tract

Question 47

What are example of topical treatment

Answer 47

``` Transcutaenous Inhalation Enema Eye drops Ear drops Intra nasal route Vaginal ```

Question 48

What is an example of enteral treatment

Answer 48

Mouth forms in tablets, capsules

Question 49

What are examples of parenteral treatment

Answer 49

Intravenous Intramuscular Subcutaneous Intra radial Transdermal: diffusion through the intact skin e.g nicotine patches Transmucosa: diffusion throuhg a mucous membrane Inhalation