1. Drugs in Health and Disease

Question 1

Definition of drug

Answer 1

A substance that acts on living tissue to produce a measurable change in tissue function (positive/negative effects)

Question 2

Drugs used in dentistry and what they do (4)

Answer 2

Local anaesthetic - prevents pain
Antimicrobials - treats and prevents infection
Anxiolytics - reduces anxiety
Analgesics - reduce post-operative pain

Question 3

Examples of hormones (4)

Answer 3

Thyroid hormones
Insulin
Cortisol
Sex hormones

Question 4

How drugs work (2)

Answer 4

Simulate/interrupt normal body communication

Act on non-host organisms to aid body defences

Question 5

Messages involved in host communication and type of information (2)

Answer 5

Hormone messages - general information to all tissues - multi-organ system
Neural messages - targeted information for specific tissues

Question 6

Role of thyroid hormones

Answer 6

Balance the body’s metabolism

Question 7

Definition of hyperthyroidism and hypothyroidism (2)

Answer 7

Hyperthyroidism - too much thyroid hormones

Hypothyroidism - not enough thyroid hormones

Question 8

Effects of hypothyroidism (5)

Answer 8

Cold intolerance
Slow mentation
Hair loss
Slow pulse
Low blood pressure

Question 9

Hypothyroidism treatment and dosage (2)

Answer 9

Thyroxine tablets - replace missing T3 and T4 thyroid hormones
Dose is adjusted to correct level gradually and it acts directly on tissues (no direct effect on thyroid glands)

Question 10

Nerve communication transmission and drugs (2)

Answer 10

Transmitted via ANS - sympathetic nervous system (adrenaline) and parasympathetic nervous system (acetylcholine)

Question 11

Nerve control of heart rate (2)

Answer 11

Sympathetic NS - adrenergic stimulation, speeds up HR via beta receptors
Parasympathetic NS - cholinergic stimulation, slows down HR via cholinergic receptors

Question 12

Autonomic drugs and type (4)

Answer 12

Adrenaline - beta-agonist/stimulator
Atenolol - beta-blocker/antagonist
Pilocarpine - cholinergic agonist - increases saliva production
Atropine - cholinergic blocker - xerostomia

Question 13

Drug/tissue interaction methods (3)

Answer 13

Receptors (coupled to ion channels, G-proteins, enzymes or gene transcription)
Enzymes
Ion channels

Question 14

Components to drug-receptor interactions (2)

Answer 14

Drug-receptor interactions

Drug-induced response

Question 15

Types of drug-receptor interactions and definitions (2)

Answer 15

Affinity - attraction between drug and receptor

Occupancy - how long (length of time) the drug is bound onto the receptor

Question 16

Type of drug-induced response and definition

Answer 16

Efficacy - how much of a response is produced

Question 17

A drug in the vicinity of a receptor will

Answer 17

Obey the law of mass action

Question 18

Definition of an agonist

Answer 18

Binds to a receptor and causes an effect

Question 19

Definition of partial agonist

Answer 19

More difficult to produce drug/receptor effect than with an agonist. AN increase in partial agonist concentration will improve efficacy of some but not others

Question 20

Definition of antagonist

Answer 20

Binds to a receptor and does not cause an effect

Question 21

Types of antagonists, definitions and examples (2)

Answer 21

Reversible - effect is reduced by increasing agonist concentration. Atenolol (beta-1 blocker)
Irreversible - binds and reduces available receptors for the agonist. Phenoxybenzamine (alpha-1 blocker)

Question 22

Enzyme action and types with examples (2)

Answer 22

Affect substrate antagonism
Reversible enzyme modification/irreversible enzyme modification
Aspirin and simvastatin

Question 23

Ion channel action and examples (2)

Answer 23

Disrupt ion balance in cell by altering electrical activity and causing an ion influx
LA and anti-diabetic drugs

Question 24

Action of LA (2)

Answer 24

Block ion channels
Inhibition of Na/K flow prevents electrical impulses from permeating the cell membrane. As pain signal is carried in this impulse, pain sensation is not felt

Question 25

Drugs act through (3)

Answer 25

Receptors on cells
Influencing enzyme action
Disruption of ion conduction channels