Pharmacology in Dentistry - Intro Flashcards
Definition of Pharmacology.
Pharmacology is the study / science of chemicals (drugs) that interact with human body
Definition of Pharmacodynamics.
Pharmacodynamics = What a drug does to the body (biological effects and mechanism of action)
Definition of Pharmacokinetics.
Pharmacokinetics = what the body does to a drug (absorption, distribution, metabolism and excretion of drugs and their metabolites)
What is a drug?
Narrowly:
Any single synthetic, or natural, substance of known structure used in treatment, prevention or diagnosis of disease.
More broadly:
Everyday substtances (caffine, nicotine, ethyl alcohol)
Illicit substances (cannabis, heroin, cocaine)
What is a Medicine?
A chemical preparation containing on or more drugs used with the intention of causing a theraputic effect. Medicines usually include agents additional to the active drug
How do drugs act?
Drugs act by binding to target molecules.
their selectivity results from:
- the chemical structure of the drug
- the target recognising only ligands of a precise structure (ligand specificity)
(a ligand is a molecule that binds to another, usually larger molecule)
It is very rare a drug has no specific target
Many drugs act by binding to regulatory proteins what are these called?
What are the other important additional targets?
Many drugs act by binding to regulatory proteins called:
- Enzymes
- Carrier molecules (transporters and pumps)
- Ion channels
- Receptors
Important additional targets are:
- RNA
- DNA
Drugs can act on receptors so what are Receptors and how are they activated?
Receptors = Macromolecules / proteins which are normally activated by transmitters or hormones
Drugs acting on receptors can either be agonists or antagonists.
Give the definition of each.
An Agonist is a drug that activated receptor and causes a response
An Antagonist is a type of drug which combines with a receptor but does not activate it, thus blocking the action of the agonist by binding to the same receptor.
Agonists bind to receptors to activate them. What is the binding step and activation step called?
Binding step = Affinity
Activation step = Efficacy
Affinity is the ‘Strength of Association’ between Ligand and Receptor.
What are the different affinity strengths you can get?
Low affinity = Fast dissociation rate (doesnt stay on receptor long)
Medium affinity = Moderate dissociation rate
High affinity = Slow dissociation rate
Efficacy is the Ability of an Agonist to Evoke a cellular Response.
What are the two efficacy levels?
Low efficacy = low response
High efficacy = high response
What do Antagonists do and what do they possess / lack?
Antagonists bind to receptors but do not activate them
Antagonists possess affinity but lack efficacy
Antagonists block receptor activation by agonists
In a graph what is the relationship between concentration (or dose) and response called?
In a graph what is the relationship between concentration (or dose) and response is hyperbolic
What is the concentration of agonist that elicits a hald maximal reponse?
EC50
in this graph:
- What are A & B
- What is the relationship between A & B in terms of potency and efficacy
- What are A & C
- What is C and its relationship with A & B in terms of efficacy
Be familiar with this graph.
