NSG 511 - Pharmacology Basic
Principles Exam 1
Pharmacokinetics - answerHow to get the drug into (absorption and distribution) through
(metabolism) and out (excretion) of the body
Membrane structure and what allows drugs to pass through - answerLipid bilayer
if water soluble it CANNOT pass through
if lipid soluble it CAN
Drugs Crossing Membranes - answerChannels and pores
-Small drugs can pass through (VERY FEW)
Transport system to move drugs across membrane (T or P-glycoprotein) P-glyco moves
drug from inside the system to the outside
Direct membrane penetration
-Drug needs to be lipid soluble
What are barriers to drugs crossing a membrane - answerPolar State
-Molecules with an uneven distribution which tends to mean water soluble
Ionization
-Not balanced
-Acids ionize in bases
-Bases ionize in acids
NEITHER WILL PASS THROUGH MEMBRANE
Absorption - answerFirst step in pharmacokinetics
Movement of a drug from site of administration into the blood
Factors that increase absorption - answerDissolution
Bigger Surface area
Blood flow
Lipid Solution
Distribution - answerThe movement of drug from blood into the interstitial space to cells
How are drugs distributed outside the vasculature - answerCapillary beds:
, -There are channels that both ionized/polar and lipid soluble drugs can get through
-P-Glycoprotein transporter takes drug INTO the blood
-T- Transporter takes drug INTO the interstitial
Blood Brain Barrier
-Glycoprotein transporter
-T-Transporter
Placenta
Protein Binding Site
Protein Binding Site for Distribution - answerAlbumin has 4 binding sites
* 25% OF DRUG IS FREE TO CROSS AND GET INTO SYSTEM
Most common drug to drug interactions is drugs competing for albumin sites
Metabolism - answerThe chemical alteration of the drug (usually by the liver) in
preparation for excretion BY THE KIDNEY
Chemical alteration is to change from lipid to water soluble
What metabolizing enzyme chemically alter the drug - answerCytochrome P450 or
CYP450
What is the most important effect of metabolism - answerHepatic conversion of drug
from a lipid to polar/water soluble form in preparation for excretion
What factors affect metabolism of drugs - answerAge (age extremes)
Liver function (transaminases)
First pass effect (drug isnt effective first time)
IF EMERGENCY GIVE IV BUCCAL OR SUBLINGUAL
Drug-drug interactions: Inhibitors and inducers of the cytochrome
Excretion - answerRemoval of the drug from the body
Factors affecting renal excretion - answerpH dependent ionizaton: AIB/BIA
Active transport
Age, GFR, and fucntion (GFR, BUN, creatine)
Principles Exam 1
Pharmacokinetics - answerHow to get the drug into (absorption and distribution) through
(metabolism) and out (excretion) of the body
Membrane structure and what allows drugs to pass through - answerLipid bilayer
if water soluble it CANNOT pass through
if lipid soluble it CAN
Drugs Crossing Membranes - answerChannels and pores
-Small drugs can pass through (VERY FEW)
Transport system to move drugs across membrane (T or P-glycoprotein) P-glyco moves
drug from inside the system to the outside
Direct membrane penetration
-Drug needs to be lipid soluble
What are barriers to drugs crossing a membrane - answerPolar State
-Molecules with an uneven distribution which tends to mean water soluble
Ionization
-Not balanced
-Acids ionize in bases
-Bases ionize in acids
NEITHER WILL PASS THROUGH MEMBRANE
Absorption - answerFirst step in pharmacokinetics
Movement of a drug from site of administration into the blood
Factors that increase absorption - answerDissolution
Bigger Surface area
Blood flow
Lipid Solution
Distribution - answerThe movement of drug from blood into the interstitial space to cells
How are drugs distributed outside the vasculature - answerCapillary beds:
, -There are channels that both ionized/polar and lipid soluble drugs can get through
-P-Glycoprotein transporter takes drug INTO the blood
-T- Transporter takes drug INTO the interstitial
Blood Brain Barrier
-Glycoprotein transporter
-T-Transporter
Placenta
Protein Binding Site
Protein Binding Site for Distribution - answerAlbumin has 4 binding sites
* 25% OF DRUG IS FREE TO CROSS AND GET INTO SYSTEM
Most common drug to drug interactions is drugs competing for albumin sites
Metabolism - answerThe chemical alteration of the drug (usually by the liver) in
preparation for excretion BY THE KIDNEY
Chemical alteration is to change from lipid to water soluble
What metabolizing enzyme chemically alter the drug - answerCytochrome P450 or
CYP450
What is the most important effect of metabolism - answerHepatic conversion of drug
from a lipid to polar/water soluble form in preparation for excretion
What factors affect metabolism of drugs - answerAge (age extremes)
Liver function (transaminases)
First pass effect (drug isnt effective first time)
IF EMERGENCY GIVE IV BUCCAL OR SUBLINGUAL
Drug-drug interactions: Inhibitors and inducers of the cytochrome
Excretion - answerRemoval of the drug from the body
Factors affecting renal excretion - answerpH dependent ionizaton: AIB/BIA
Active transport
Age, GFR, and fucntion (GFR, BUN, creatine)
