Pharmacodynamics and Pharmacokinetics Flashcards
Activation of protein receptors causes a ________________.
Conformational change
What is the drug effect related to?
The number of bound receptors.
Ie: Paralytics
____________ activates receptors by binding to them.
Agonist
What are 3 reversible bonds?
What bond is irreversible?
Ion (opposite charges), Hydrogen (electronegative atoms), and Van der Waals interaction (repulsive attraction)
Covalent bonds (strongest bond)
____________ binds to a receptor but does not activate the receptor, the get in the way of the endogenous ligand.
Antagonist
Increasing amounts progressively inhibit the agonist and shift the dose-response curve to the right.
Competitive antagonism
Even high concentrations of agonist can’t cause the agonist event.
Noncompetitive antagonism
Binding to a receptor (usually at agonist site).
Causes less response than the agonist even at a supramaximal dose.
Partial Agonist
Compete for the same site as the agonist but produces the opposite effect.
Inverse Agonist
Even high concentrations of agonists can’t cause the agonist event.
Noncompetitive antagonism
The number of receptors are not __________.
Static
Receptors can increase or decrease depending on comorbidity and drug therapy
What is tachyphylaxis?
Quick tolerance, down-regulation of receptors.
In pheochromocytoma, there is a ___________ in beta receptors in response to an increase in ____________.
decrease; catecholamines
Tolerance builds up
Receptors are classified by _____________.
Location
What 3 areas can receptors be located?
Lipid Bilayer
Intracellular Proteins
Circulating Proteins
Most of the anesthetic drugs that we give have receptors located in the _____________.
Examples?
Lipid Bilayer (Membrane Bound)
Opioids, BZDs, Beta-blockers, catecholamines, NMBD.
What are examples of drugs that bind to intracellular proteins?
Insulin, Steroids, Milrinone
What are examples of drugs that bind to circulating proteins?
Anticoagulants
Anticoagulants that are free or unbound will cause drug effect
What is the quantitative study of injected and inhaled drugs and their metabolites? What the body does to the drug.
What are the 4 components?
Pharmacokinetics
Absorption
Distribution
Metabolism
Excretion
Pharmacokinetics determines the concentration of the drug in the ____________ and at the _______________. This varies significantly from patient to patient.
Plasma and Effector Site
What is the one-compartment model?
Immediately after drug injection, the concentration of the drug is diluted by plasma in a central compartment, resulting in a small volume of distribution, and excreted immediately.
What is the vessel-rich group?
A small percentage of the body mass (brain, kidney, heart, lungs) that makes up a large percentage of cardiac output.
What is the two-compartment model?
The drug goes into a central compartment and then peripheral compartments (muscles, fats, tendons, ligaments).
For plasma protein receptors, what do acidic drugs bind to?
What do alkalotic drugs bind to?
Acidic drugs bind to albumin.
Alkalotic drugs bind to Alpha 1- Acid Glycoprotein.
Only __________ drug can cross cell membrane (distribution) and can determine the concentration available to receptor (potency)
Free unbound drug
Name factors that can decrease plasma protein.
Age
Hepatic Disease
Renal Failure
Pregnancy
Burns
Sepsis
If the normal free fraction of the drug is 2% and half the plasma proteins are lost, then the free fraction of the drug is _______%.
4%, it doubles.
Poor protein binding and lipophilic drugs have a ____________.
Examples
Greater Volume of Distribution (escapes plasma)
Examples: Thiopental and Diazepam
Highly protein-bound drugs to plasma protein will result in a ____________.
Examples
Smaller Volume of Distribution (stays in plasma)
Example: Warfarin
What is metabolism?
Usually conversion of an active drug to an inactive drug from lipid-soluble drugs to water-soluble and inactive metabolites (usually). Then kidneys pee it off.