Intro to clinical pharmacy and drug action

Question 1

what is a drug?

Answer 1

chemical substane that when administered to a living organism produces a biological effect on the structure or function of the body

Question 2

name and describe the three effects of drugs

Answer 2

therapeutic effects
* intended outcome of drug
side effects
* unintended effects that does not hinder primary effect
adverse effects
* undesireable effects that can hinder treatment

Question 3

what types of drugs are used in dentistry and what are they used for?

4

Answer 3

local anaesthetic - lidocaine
* prevent pain during procedures
antimicrobials - penicillin
* treat and prevent infections
anxiolytics - diazepam
* reduce anxiety
analgesics - paracetamol
* reduce post-operative pain

Question 4

what can drugs do?

3

Answer 4

simulate normal body communications
interrupt normal body communuications
act on non-host oraganisms to aid body defences

Question 5

what ways does communication occur within the body?

2

Answer 5

hormone messages - general information to ALL tissues
neural messages - targeted information to SPECIFIC tissues

Question 6

what are the different ways of drug administration?

8

Answer 6

topical - applied to tissue where it acts
systemic - applied to whole organism
parenteral - administered by injection
transdermal - applied to skin for adsorption
subcutaneous - injected into tissues of the skin
intramuscular - injected into muscle
intravenous - injected into vein
transmucosal - applied to mucosa for adsorption

Question 7

what are autonomic drugs?

Answer 7

drugs that enhance or inhibit the function of the sympathetic or parasympathetic nervous system

Question 8

how do drugs work?

4

Answer 8

activating or blocking receptors
activating or blocking enzyme function
opening or blocking ion channels
facilitation or blocking transport systems

Question 9

what is drug efficacy and what is it determined by?

3

Answer 9

drug efficacy: how effective the drug is at producing a response from the receptor
determined by: affinity (how avidly the drug binds to the receptor) and occupancy (how much time the drug spends on the receptor)

Question 10

what is an agonist?

Answer 10

binds to the receptor and initiates the same action that would be produced by the substance (neurotransmitter or hormone) which would normally bond together

Question 11

what is a partial agonist?

Answer 11

binds to the receptor but partially activates the receptor so it has less efficacy in comparison to the agonist - produces less than moximal effect but increase in concentration may improve efficacy

Question 12

what is an antagonist?

Answer 12

binds to but does not activate the receptor so blocks or reduces the response

Question 13

what is a non-competitive antagonist?

Answer 13

binds to the allosteric site and prevents activation of receptor

Question 13

what is a competitive antagonist?

Answer 13

binds to the same site on the receptor as the agonist so blocks it’s action

Question 14

what is the difference between reversible and irreversible antagonists?

Answer 14

reversible - binds non-convalently and can be displaced by increasing the concentration of the agonist
irreversible - binds tightly so cannot be displaced so reduces available receptors for agonist

Question 15

what are enzymes?

3

Answer 15

proteins that speed up chemical reactions in the body
remains unchanged at the end of their normal reaction
may build up or break down existing substances

Question 16

what are the effects of drugs on enzymes?

2

Answer 16

competitive substrate antagonism - drug competes with the substrate to bind to the enzyme
non-competitive substrate inhibition - drug binds to allosteric site, causing conformational change in the enzyme structure which prevents substrate binding