Shared Flashcard Set

Details

Pharmacokinetics
Pharmacokinetics/ drug absorption
44
Pharmacology
Undergraduate 2
12/30/2010

Additional Pharmacology Flashcards

 


 

Cards

Term
Pharmocokinetics
Definition
Drug movement into, within and out of the body, which includes absorption, distribution, and elimination
Term
Pharmacodynamics
Definition
drug actions and their mechanisms
Term
Prodrugs
Definition
these drugs are inactive upon administration, but the metabolites become the active form.
Term
Passive diffusion
Definition
What is the primary means by which drugs cross membranes?
Term
Lipid-water partition coefficient (Kp)
Definition
the ratio of the concentration of the drug in two immiscible phases: a nonpolar liquid (representing membrane) and an aqueous buffer (representing the plasma)
Term
[drug] in lipid phase/ [drug] in aqueous phase
Definition
Kp=
Term
R-COOH, R-OH, R-SH
Definition
What are the functional groups of weak acids?
Term
R- NH2
Definition
What is the functional group of a weak base?
Term

H⁺+A

Definition
for weak acids, HA= _________
Term
B+H⁺
Definition
For Weak Bases: BH⁺=_________
Term
pKa
Definition
the pH at which half of the molecules are in the ionized form and the other half are in the unionized form 
Term
only the unionized form
Definition
What form of a drug may be transferred across the membrane via passive diffusion?
Term
HA and BH⁺
Definition
when pH < pKa what are the predominate forms of acids and bases?
Term
A⁻ and B
Definition
when the pH>pKa what are the predominate forms of acids and bases? 
Term
filtration
Definition
Passage of molecules through pores or porous structures as in the renal glomerulus and capillary endothelium cells
Term
carrier-mediated transport
Definition
The drug combines with a transport protein in the membrane and the complex can move across the membrane 
Term
Active transport
Definition
this type of carrier-mediated transport has reversible binding, it is selective, requires ATP, it's a one-way process, it can be saturated and it can be inhibited
Term
Facilitated diffusion
Definition
this type of carrier-mediated transport is selective, can be saturated, does not require ATP, and is bi-directional with no drug accumulation on either side
Term
Receptor-mediated endocytosis
Definition
The binding of some peptide hormones, growth factors, antibodies, and other substances to their receptors on the cell surface can trigger a process of endocytosis that brings both the receptor and the ligand into the cell.
Term
oral, sublingual, rectal
Definition
What are the types of enteral administration routes?
Term
intavenous (IV), Intramuscular (IM), Subcutaneous (SC)
Definition
what are the routes for parenteral drug administration?
Term
first pass effect
Definition
drugs administered orally are first exposed to the liver and may be extensively metabolized before reaching the rest of the body
Term
Mouth
Definition
this drug absorption site is best for potent drugs that are lipid soluble. Transfer occurs by passive diffusion, and the drugs can bypass the first-pass effect.
Term
Stomach
Definition

Drugs absorbed here will experience first pass effect.

- Transfer occurs via passive diffusion

-Weak acids are absorbed better here, and weak base dugs will become trapped. 

Term
Small Intestine
Definition
Because of the large amount of surface area, this is the primary site of absorption for most drugs. Absorption occurs by passive diffusion, active transport, facilitated diffusion, endocytosis, and filtration
Term
Large intestine
Definition
This site is not very important for drug absorption, it may occur if the drug is not absorbed effectively in the small intestine
Term
Bioavailability
Definition

-fraction of administered drug that reaches the systemic circulation. 

-reduced by first pass effect, and altered by changes in GI motility.

Term
70%
Definition
If you have a 100mg drug and only 70mg is transported to the circulatory system, what is bioavailability?
Term
binds to plasma proteins
Definition
When a drug does this, it can no longer go to its receptor at the site of action, cant be distributed to body tissues, cant be metabolized by enzymes, and cant be excreted from the body
Term
inactive
Definition
Bound drugs are pharmacologically _________
Term
Albumin
Definition
the primary serum protein responsible for drug binding. The strongest affinity for weak acid.
Term
Lipoproteins
Definition
Lipid-soluble drugs. The binding capacity is dependant on their lipid content.
Term
alpha 1-acid glycoprotein
Definition
this glycoprotein is produced by acute injury, trauma, or stress. It has a 5.5 day half time. This glycoprotein may interfere with basic drugs and cause side effects after the time of the half life.
Term
kidney, liver
Definition
where are the primary sites for drug excretion?
Term
unionized, lipid soluable
Definition
In the kidney, what types of drugs will undergo passive reabsorption?
Term
forced alkaline diuresis
Definition
administering a bicarbonate will increase renal excretion of a weak acid drug
Term
ammonium chloride
Definition
administering this will decrease the pH and increase the ionization of weak base drugs
Term
lipid insoluble or ionized drugs
Definition
What types of drugs undergo excretion from the liver?
Term
eterohepatic cycling
Definition
What happens to lipid soluble drugs in the liver?
Term

Non-synthetic reactions

Synthetic reactions

Definition
What are the two types of reactions in drug metabolism?
Term

1. oxidation reaction

2. reduction

3. Hydrolysis

Definition
Name the types of non-synthetic reactions
Term
Oxidation reactions
Definition
This drug metabolism reaction is a direct insertion of a hydroxyl functional group into the drug molecule mostly by cytochrome P450. It occurs almost exclusively in the endoplasmic reticulum of the liver. 
Term
synthetic reactions
Definition
this drug metabolism reaction is a conjugation with a cugar, and amino acid or sulfate- more water-soluable compounds and more excretion of the drug
Supporting users have an ad free experience!