Module 1 Flashcards
Pharmacodynamics
What are pharmacodynamics?
how a drug changes the body. Focused on mechanisms of action and relationships between drug concentration and responses in the body
What is the frequency distribution curve in pharmacodynamics?
A graph showing if drug; worked or not
What is the median effective dose (ED50) in pharmacodynamics?
- drug required to produce specific therapeutic response in 50% of clients
- average dose does not apply to everyone
What is the median lethal dose (LD50) in pharmacodynamics?
- the dose of drug that would be lethal in 50% of patients
What is the median toxicity dose (TD50) in pharmacodynamics?
- the dose required to produce given toxicity in 50% of patients
What is dose-response relationship in pharmacodynamics?
- Phase I = very few target cells are affected by drug
- Phase II = shows linear relationship between drug and response
- Phase III = plateau, where no further response occurs with higher does
What is potency in pharmacodynamics?
the measure of drug activity or “power”. The more potent = less is needed
What is efficacy in pharmacodynamics?
the ability to produce the desired result
What are drug receptors?
When cells receive information form their environment through receptors to cause a response
Types of drug receptors responses?
- ligand = a molecule that binds to a receptor
- affinity = the face by which atoms are health together -> the strength of attraction between a receptor and a ligand = magnet
- agonist = drug that produces the same type of response as an endogenous susbstance (> or = response)
What is a drug interaction?
when a substance increases or decreases a drugs action
3 types of drug interactions in pharmacodynamics
- additive effect = 2 drugs that provide the same therapeutic action are combined (2 antihypertensives)
- synergistic effect = effect of 2 drugs combined is greater than would be expected than just adding the 2 individual drug actions
- antagonistic effect = 2 drugs have opposite effects
What is drug tolerance?
increasing the dosage of a drug to produce the same magnitude of effect
What is drug dependence?
- physical dependence = when the body adapts to repeated use of a substance - altered environment as normal
- when they stop taking the drug abruptly they experience withdrawal
What are the 4Cs of addiction?
- craving
- loss of control
- compulsion of use
- use despite of consequences