Principles and how to learn pharmacology Flashcards
Pharmacology
what is this a study of?
Pharmacology is the study of the effects of chemical substances called drugs on living organisms
drug
what are they (2)
Chemicals that produce biological effects
Chemicals that are ‘given’
Why is it so important?
what do they reduce?
what do they improve?
Drugs used throughout healthcare profession as they reduce patient morbidity and mortality
Drug improve patient care and outcomes
Diagnostic skills of healthcare professions are helpless
unless drugs are prescribed properly
Clinical errors are often result of poor prescribing
Pharmocodynamics (2)
What drug does to body, its mechanism of action
Pharmokinetics (4)
What body does to drug, how drug is absorbed, distributed, metabolised and excreted (ADME)
clinical uses
What drug can be used for
Adverse effects and Contraindications
Potential problems with drug
Aspirin
pharmacodynamics - what it does to body
primary (3)
secondary
research?
Pharmacodynamics : What it does on the body
Primary
analgesic (pain killer)
anti-pyretic (reduce fever)
anti-inflammatory (reduce immune response)
Secondary
anti-platelet aggregation in low doses (reduce bloods clots)
Research
possible actions of reducing cancer of colon and rectum?
delays onset of Alzheimer’s disease?
Aspirin
pharamcodynamics - mechanism of action
site of action? what does it inhibit?
effect of this?
effect of these? (5)
net effect? (4)
How does it produce its effects - Mechanism of action
Where is its site of action
Inhibits enzyme called cyclooxygenase (COX)
What does COX do?
COX catalyses the breakdown of arachidonic acid into prostaglandins (PGs) and thromboxane (TXAs)
What do PGs and TXA do?
PGs that have a wide range of effects including:
Sensitising pain nerve endings – cause pain
Dilating blood vessels – redness, inflammation
Increasing blood vessel permeability – swelling, cause pain
Setting body temperature - produce fever, feeling of being unwell
TXA causes platelet aggregation
So, aspirin prevents these actions
Hence analgesic, anti-inflammatory,
anti-pyretic and anti-platelet aggregation actions
Aspirin : Pharmacokinetics
routes of administration?
where is it readily absorbed?
metabolised where? by?
excreted in?
How does a drug get into the body and what happens to it
Routes of administration - there are many routes available
e.g. oral IV, IM, SC, inhalation
Readily absorbed from stomach and intestine
Metabolised in liver by esterase’s, some excreted unchanged, half-life of 4 hours in low doses
Excreted in urine
This information is essential for deciding
dose and how often drug is administrated
Aspirin : Clinical Uses
4 uses and examples
Analgesia e.g. headaches, toothache, dysmenorrhoea
Reduce fevers (makes you feel ill)
Acute and chronic inflammation, e.g. rheumatoid arthritis
To reduce platelet aggregation after myocardial infarction, many patients take it for life
Aspirin : Adverse effects (unwanted effects)
4 key side effects
what are they?
Gastrointestinal irritation and bleeding
Might be severe in some individuals (side effect)
Not given chronically
Tinnitus, vertigo, nausea and vomiting High doses (side effect)
Should be avoided in asthmatics – stimulates attack
This is a contraindication
May cause Reye’s syndrome in children
Can be fatal
Do not give to young children - Contraindication
