Chapter 2 Flashcards
What does the line on the does curve represent?
- relationship between amount of drug (x-axis) and response to the drug (y-axis)
What is the log phase ?
This is when the dose has minimal increase response
What is Proportional phase?
When the increase dose is equlal to the increase response
What is the saturation phase?
When the increase dose no longer causes increase response.
Where is the ED50 (effective doses) located?
On the x-axis
True/ False: The increase dose equals to increase side effects.
True
What is drug potency?
The amount of a drug needed to produce a desired effect.
This is on the x-axis
What is Drug efficacy (response)?
Whether a specific drug reaches a maximal effect when administered regardless of potency.
If the response of 3 drugs are at 50% but each does is different. Which one would be the most potent?
The drug with the lowest dose will be the most potent.
Increasing potency = decrease in ED50.
Calculating lethal does is only calculated on?
Animals
What is the therapeutic index?
- Helps determine the likelihood of toxicity before clinical trials
- Can only be determined in animals
- TI greater than 10 are required for clinical trials
What is pharmacodynamics?
Is how the drug afffects the body or how does the drug causes therapeutic effects.
Drugs bind to receptors on or in the cell but how?
- Must have an appropriate receptor and appropriate cells in the body to respond to medication.
- Receptor naturally occurs in the body
What type of effects we want to happen to the body when taking medications?
To help bring the body back to homeostasis
What does the plasma (cell) membrane regulates?
The entry of molecules into the cell
What type of layer is the plasma membrane?
It is a lipid bilayer
What are the different parts of the cell membrane?
extracellular fluid
green: protein
Top layer is hydrophobic
Middle: hydrophobic/lipophilic
Bottom- Hydrophilic
Cystoplasm
Hydrophilic drugs bind to ?
Cell-Surface receptors
What are the two types of channels within a cell?
- Fast channels: ligand-gated channel
- Voltage-gated channel
How does the fast channel open?
- Open when signal molecule binds
How does voltage-gated channels open?
Opens when membrane potential changes.
Drugs can be what?
- Hydrophilic or lipophilic
What determines a drug type and how it interacts?
chemical propertied of the drug determine how the drug interacts with the plasma membrane.
What does hydrophilic mean?
- water soluble
- good for traveling through blood
- bad for getting through membranes
How does hydrophilic drugs binds to receptors?
It has to bind to receptors on the cell surface which causes a change to the receptor then in turn causes a change to what happen to the cell.
What are the two types of messenger systems for hydrophilic drugs?
- First messenger (drug) binds to the cell surface receptor
- Second messenger is inside the cell and directly causes an intracellular response
What is a lipophilic ?
- fat soluble
- bad at traveling through the blood
- good at getting through membrane because it binds to receptors into cytoplasm.
What occurs because lipophic drugs bind to cytoplasmic receptors?
- drug/receptor complex moves into the nucleus and binds to DNA which causes a chane in gene expression/ changes in transcription.
What are agonist and antagonist act on cellular receptors.
- Agonists induces a cellular response (causes something to occur within the cell): Full agonist= 100% response, Partial= 50%
- Antagonists blocks a cellular response
What are the different types of antagonists?
- Competive: binds to the same site as the agonist and prevents the agonist from binding
- Noncompetive: binds to receptor outside of agonist binding sites and reduces agonist activity through other mechanisms
What are ligands?
They are molecules that binds to a receptor and activates it.
What are natural ligands?
Normal molecule that binds to a receptor and equals a 100%/. full response.
What are artifical ligands
A medication that binds to the receptor
Which two substances works the same?
Natural ligands and full agonist?
True/ False: All agonist are ligand?
True
What is impotant to its mechanism of action?
The chemical structure of drugs
Drugs act through what in the body?
Receptors
Hydrophilic drugs uses?
cell-surface receptors
Lipophilic drugs uses ?
cytoplasmic receptors
What is the does drugs affect?
homeostasis
What is pharmcokinetics?
- How the body affects the drugs through
1. ADME
2. Absorption
3. Distribution
4. Metabolism
5. Excretion
Molecules with ionic bonds form?
Hydrophilic drugs (SALTS)
Chemical bonds in a molecule determine what?
whether a drug is Hydrophilic or lipophilic
Which bonds can change molecules that interact with water and are hydrophilic?
Ionic bonds: electrons transfered from one atom to another. (forms oppositely charged ions)
Polar covalent bonds: electrons shared unequally. ( partically changed atoms on either side of the bond.
Which bond is lipophilic?
Nonpolar covalent bonds- electrons shared equally between two atoms
What is diffusion ?
Is the movement of a molecule across the plasma membrane down its concentration gradient.
What is the movement of diffusion?
movement from high concentration to low concentration.
NO ENERGY REQUIRED
What is simple/ positve diffusion?
llipophilic drugs that crosses membrane
Facilitated diffusion is?
hydrophilic drugs crossing the membrane, while using the protein as transport (carrier or channel).
What is active transport?
The movement of a molecule or ION across the plasma membrane up its concentration gradient
What is ionized drug?
electrically charged at a particular pH.
has hydrophilic properties and bad at crossing membranes
What are non-ionized drugs?
electrically neutral at a particular pH.
has good crossing membranes
