1. Drugs in Health and Disease Flashcards
Definition of drug
A substance that acts on living tissue to produce a measurable change in tissue function (positive/negative effects)
Drugs used in dentistry and what they do (4)
Local anaesthetic - prevents pain
Antimicrobials - treats and prevents infection
Anxiolytics - reduces anxiety
Analgesics - reduce post-operative pain
Examples of hormones (4)
Thyroid hormones
Insulin
Cortisol
Sex hormones
How drugs work (2)
Simulate/interrupt normal body communication
Act on non-host organisms to aid body defences
Messages involved in host communication and type of information (2)
Hormone messages - general information to all tissues - multi-organ system
Neural messages - targeted information for specific tissues
Role of thyroid hormones
Balance the body’s metabolism
Definition of hyperthyroidism and hypothyroidism (2)
Hyperthyroidism - too much thyroid hormones
Hypothyroidism - not enough thyroid hormones
Effects of hypothyroidism (5)
Cold intolerance Slow mentation Hair loss Slow pulse Low blood pressure
Hypothyroidism treatment and dosage (2)
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)
Nerve communication transmission and drugs (2)
Transmitted via ANS - sympathetic nervous system (adrenaline) and parasympathetic nervous system (acetylcholine)
Nerve control of heart rate (2)
Sympathetic NS - adrenergic stimulation, speeds up HR via beta receptors
Parasympathetic NS - cholinergic stimulation, slows down HR via cholinergic receptors
Autonomic drugs and type (4)
Adrenaline - beta-agonist/stimulator
Atenolol - beta-blocker/antagonist
Pilocarpine - cholinergic agonist - increases saliva production
Atropine - cholinergic blocker - xerostomia
Drug/tissue interaction methods (3)
Receptors (coupled to ion channels, G-proteins, enzymes or gene transcription)
Enzymes
Ion channels
Components to drug-receptor interactions (2)
Drug-receptor interactions
Drug-induced response
Types of drug-receptor interactions and definitions (2)
Affinity - attraction between drug and receptor
Occupancy - how long (length of time) the drug is bound onto the receptor
Type of drug-induced response and definition
Efficacy - how much of a response is produced
A drug in the vicinity of a receptor will
Obey the law of mass action
Definition of an agonist
Binds to a receptor and causes an effect
Definition of partial agonist
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
Definition of antagonist
Binds to a receptor and does not cause an effect
Types of antagonists, definitions and examples (2)
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)
Enzyme action and types with examples (2)
Affect substrate antagonism
Reversible enzyme modification/irreversible enzyme modification
Aspirin and simvastatin
Ion channel action and examples (2)
Disrupt ion balance in cell by altering electrical activity and causing an ion influx
LA and anti-diabetic drugs
Action of LA (2)
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
Drugs act through (3)
Receptors on cells
Influencing enzyme action
Disruption of ion conduction channels
