Card Set Information
What is the basic tenet of pharmacology?
For most drugs their effects are directly proportional to the concentration of their active forms at receptors
Time to onset of effect
time to peak effect
duration of action
What are the factors controlling concentration of active form of a drug at its receptor?
Therefore the time response curve
the movement of drug from the site of application into the bloodstream
The movement drug between blood and tissues
the conversion of drug to metabolites
the removal of drug from the body to the external environment
What is the dose of drug determined by?
The inherent potency of the drug
What does the frequency of the dose depend on?
Drug clearance rate (elimination)
Desired/Target plasma drug concentration
What does pharmacokinetics depend on?
What does pharmacodynamics?
What is the degree of ionization controlled by?
pH of surrounding aqueous phase
whether the drug is a weak acid or weak base
cannot get through membranes
can diffuse through membranes
T/F Molecules are better absorbed at a pH where there is 50% Nonionized
T which is the same as the pka value
What are the three structures for absorption?
Folds of Kerckring
What is the main factor affecting absorption?
routes of administration
What are the routes of administration?
What are the factors affecting oral absorption?
Disintegration of dosage form
Dissolution of particles
Chemical stability of drug
Stability of drug to enzymes
Motility and mixing in GI tract
Presence and typ of food
Blood flow to the GI tract
Gastric emptying time
What are the pharmacokinetic parameters?
Area under the time concentration curve
Measures the extent of drug available in systemic circulation
The observed maximum concentration of drug
Measure of both the rate of absorption and the extent of drug available in systemic circulation
The time after administration of drug at which Cmax is observed
Measure rate of absorption
area under the moment curve
Integral product of time and plasma concentration
Mean residence time
The average total time molecules of a given dose spends in the body
What is biopharmaceutics?
Study of physical and chemical properties of drugs and their proper dosage as related to the onset, duration, and intensity of drug action under physiological or pathophysical conditions
How are particle size and surface area
They are inversily proportional!!!!!
What is the effective surface area?
The area of solid surface exposed to the dissolution medium