INTRODUCTION Flashcards
Many drugs found in nature are________-
Alkaloids
- alkaline pH
- amine group in their stuctures
Most drugs have MW between _________
100 and 1000
Substances that act on biologic systems at the chemical (molecular level) and alter their funcctions
Drugs
The molecular components f the body with which drugs interact to bring about their effects
Drug receptors
The phase of drug movement from the site of administration into the tissues
Distriibution phase
The phase of drug inactivation or removal from the body by metabolism or excretion
Elimination phase
movement of molecule through a bioloic medium
PErmeation
a specialied molecule, usually a protein that carries a drug, transmitter, or other molecule across a membrane in which it is not permeable
Transporter
If drug receptor results in activation of the receptor, the drug is termed as
agonist
if inhibition results in binding to te receptor
Antagonist
A receptor molecule may have several binding sites. Quantitation of effects of drug receptor interaction as a function of dose (or concentration) yield _____________
Dose response curves
Drugs bind to some nonregulatory molecules in the body without discernible effects. There are called ______-
inert receptors
movement of molecules through the watery extracellular and intracellular spaces
Aqueous diffusion
governed by FICK’s Law
passive movement of molecules through lipid bilayer membranes
Lipid diffusion
governed by Ficks law
Occurs through binding of the molecule to specialized components on cell membranes with subsequent internaliation by infolding of that area of the membrane
Endocytosis
- Very large or very lipid insoluble materials
Predicts the rate of movement of molecules across a barrier.
- concentration gradient (C1-C2)
- permeability coeffiient
- area and thickness of the barrier
Fick’s Law
- Drug absortption is faster within organs with large surface area
- Drug absorption is faster in those with thin membranes
The aqueous solubility of a drug is often a function oof the __________
electrosatic charge
Lipid solubility is __________proportional to its charge
Inversely
Henderson-hasselbach equation
WEak bases are _________
Ionized
- more polar and more water soluble
Weak acids are _________
not ionized
- Less water soluble when they are protonated
High blood flow maintains a _________ concentration gradient between drug depot and blood
high
- facilitates absorption
the _______ is applied to drug excretion in the urine
Hendrson-hasselbach principle
The size of organ determines the _______between blood and the organ
Concentrtion gradient
