Mechanism of Drug Action Flashcards
What is a drug?
A drug is a chemical or substance that causes changes in the structure or function of living organisms
What is a medicine?
A medicine is the vehicle for administration of the duyge (active ingredient) to the human or animal e.g. tablet, capsule, injection, ointment, inhaler, suppository etc.
What is the Greek word for a drug
Pharmakon
What is the generic name/INN of a drug?
International Nonproprietary name
Standardised internally recognised name for a drug e.g. omeprazole, salbutamol
What is the trade/brand name of a drug?
Name given by the original manufacturers e.g. Ventolin, Losec
How long is a drug on patent?
10 years
What happens when a drug comes off patent?
Anyone can make the drug
What is pharmacology?
The science of drugs actions and uses, but has a number of sub-disciplines
What are the sub-disciplines?
Pharmacodynamics, pharmacokinetics,m therapeutics, toxicology, pharmacoepidemiology, pharmacogenetics, pharmacoeconomics
What is pharmacodynamics?
Focus on mechanism of drug action “what the drug does to the body”
What is pharmacokinetics?
Movement of the drug within the body “what the body does to the drug”
What does the mechanism of action of drugs mean?
Specific molecular processes by which drugs work
What does the mode of action of drugs mean?
General description of the type of action e.g. antihypertensive, antidepressant
What is the site of action of drugs?
Specific organs, tissues or cells affected by the dru ge.g. Bronchi, sensory neurons
What is a risk versus benefit assessment?
Every decision to use a drug requires an assessment of risk versus benefit - knowing how a drug achieves its action allows us to predict both its beneficial and unwanted effects
What are the rules of cellular society?
Each cell has its own specific function
It accepts communication (signals) from its own and other organs
It interprets those signals correctly
It responds to those signals appropriately
It transmits its own signals to other cells
What are signal molecules also known as?
Ligands
What do signal molecules include?
Neurotransmitters (noradrenaline, dopamine)
Local hormones or autocoids (histamine, prostaglandins)
Cytokines (interprefons, interleukins)
Hormones (thyroxine, insulin)
What is the second-messenger system?
Ligand-receptor binding causes further signalling within the cell and alteration in cell function (eg. myocardial cell contracts)
Do ligands bind reversibly or irreversibly with receptors?
Reversibly
What drugs do not have a specific receptor?
Antacids and diuretics
What are drug targets or receptors?
Proteins that have a specific chemical configuration or ‘shape’ that is recognised by the appropriate logan or drug
Where are drug targets/receptors found?
Cell membrane receptors, cell nucleus receptors, ion channels, enzymes, carrier molecules (transporter)
What are the mechanisms that cease ligand effects?
Enzymatic degradation of drug or ligand (e.g. acetylcholine broken down by cholinesterase)
Reuptake back into cells from which released (e.g. serotonin)