Module 7 Flashcards
The theoretical volume that would be necessary to contain the total amount of an administered drug at the same concentration that it is observed in the blood.
volume of distribution
If the dose is 10 mg and Cp is 20 mg/L, the apparent volume of distribution is:
0.50 L
The half-life of a drug is 3 hours, the rate constant of elimination is:
0.231/hr
The two most important sits for drug elimination are:
Liver and kidney
What is the fraction of unchanged drug reaching the systemic circulation?
Bioavailability
Type of drug that as affinity for a receptor but poor efficacy
antagonist
Type of drug that binds to a receptor and activates it
agonist
When the rate of drug input is equal to the rate of drug elimination, this is called:
Steady state
The main enzymes involved in metabolism:
The cytochrome p450 family
Considered the most common Phase II reaction:
Glucuronidation
This metabolite is highly reactive and responsible for acetaminophen-induced hepatotoxicity:
NAPQI
Methanol toxicity produces a decrease in blood pH because of its toxic metabolite. This metabolite is:
Formic acid
Most of the ethanol in the body is broken down in the liver by an enzyme called:
Alcohol dehydrogenase
What phase of metabolism: Oxidation, reduction, hydrolysis:
Phase I metabolism
1,4-butanediol is a metabolic precursor to:
GHB
Bind to locations on an enzyme away from the active site, inducing a conformational change that increases the affinity of the enzyme’s active site(s) for its substrate(s).
Allosteric activators
Modify the active site of the enzyme so that substrate binding is reduced or prevented.
Allosteric inhibitors
Actions of the drug on the body
Pharmacodynamics
Actions of the body on the drug
Pharmacokinetics
States that the rate at which a molecule moves through a material is proportional to the concentration gradient between the two ends of the material; and inversely proportional to the thickness of the membrane.
Fick’s Law of Diffusion
The metabolism of drugs or chemicals in liver or intestine prior to their reaching the systemic circulation.
First Pass Elimination
Refers to the removal of drug from plasma
Clearance
What 3 things may influence clearance?
Dose, Organ Blood Flow, Function of Liver or Kidneys
The process whereby a drug in the liver is secreted into the bile, stored in the gall bladder, and subsequently released into the small intestine, where the drug can be reabsorbed back into circulation and subsequently returned to the liver.
Enterohepatic Circulation
A constant fraction of drug is removed from the blood per unit time
First-order elimination
A constant amount of drug is cleared from the blood per unit time
Zero-order elimination