Pharmacology 1 Flashcards
(41 cards)
What is Pharmacology
Defined as the study of substances that interact with living systems thro chemical processes, especially by binding to regulatory molecules and activating or inhibiting normal body processes
What is a drug
Defined as a natural product, chemical substance, or pharmaceutical preparation intended for administration to a human or animal to diagnose or treat a disease
How does the body handle drugs
ADME
Absorption, distribution, metabolism, elimination
What are pharmacokinetics
how the body handles the drug
Bioavailability
The fraction of the administered drug that reaches the systemic circulation
Onset of Action
Time after administration at which you see the drug effect
duration of action
time during which plasma concentration stays above the MEC for desired effect
half-life
time required for plasma concentration of a dug to decrease by 1/2 after absorption and distribution are complete
Therapeutic Window
Where you want to effects to occur. it above the MEC for desired response and below the MEC for adverse response
Whats the MEC
Min effective concentration
What happens during distribution
After reaching the blood stream, drugs get distributed into various tissues in the body in two phases
Initial phase of distribution
Distribution to interstitial and intracellular space, and to highly perfused organs such as liver, kidney and brain
Second Phase of distribution
Distribution to muscles, most viscera, skin, bone and fat that is slower
What does drug metabolism (biotransformation) do
Enhances elimination of drugs by increasing their excretion, terminate the action of drugs and endogenous substance and activates certain prodrugs to their active form
Where are the sites of metabolsim
Mainly in the liver, kidneys play an important role in the metabolism of some drugs, a few are done in blood and intestinal wall
What are the two forms a drug can be in when excreted
it could be unchanged or it can be converted to metabolites
what kind of compounds do excretory organs expel best (lungs exuded)
Polar compounds are excreted much easier than substances with high lipid solubility
What must happen to lipid soluble drugs to be eliminated
they must be metabolized to more polar compounds before they can be excreted
What kind of drugs are excreted in feces
Unabsorbed oral drugs or drug metabolites excreted either in the bile or into the intestinal tract and are not reabsorbed
Why is excretion of the lungs important
Mainly for the elimination of anesthetic gases and volatile compounds such as ethanol
whats the most important organ for excreting drugs and their metabolites
the kidneys
What is Pharmacodynamics
Study of what drugs do to the body. Drug effects, mec of action, measurement of drug action, modulation of drug action
what are some common drug targets
receptors, enzymes, carrier molecules, voltage-gated ion channels
What are receptors as drug targets
A structure on the surface of a cell (or inside a cell) that selectively received and binds a specific substance causing a change in cell function
