Advanced Pharmacology Exam 1 TESTS WITH ANSWERS A+ GRADE.
What is pharmacokinetics? What are its 4 categories? - What the body does to the drug
1. Absorption
2. Metabolism
3. Distribution
4. Excretion
Quickest route of absorption? Slowest? - IV = quickest
IM = slowest
What is the most common way drugs pass through cell membranes? - Passive diffusion
What characteristics of a drug allow it to pass most quickly through cell membranes (usually through
passive diffusion)? - Small, uncharged (unionized), lipid soluble--pass through membrane without any
energy
What does it mean when a drug is ionized? - It means that the drug is stuck in the compartment it was
ionized in and has to be moved to the next compartment (cannot be absorbed into the bloodstream)
Where do weak acids absorb? - Stomach
Where do weak bases absorb? - Small intestine
pH of stomach: - 2-4
pH of small intestine: - 6-7
pH of large intestine: - 6-7
,pH of bloodstream: - 7.35-7.45
pH of bladder: - 5-8
pH of breastmilk: - 7.1
Where will a drug absorb if it is a weak base that ionizes at a pH of 4 and lower? - In the small intestine
(since the stomach has a pH of 2-4, so the drug will become ionized and move to the small intestine
where it will be able to absorb into the bloodstream)
How can we manipulate the urine pH in cases of overdose? - Drugs that are weak acids (aspirin) can be
trapped and excreted through the urine.
We raise pH of the urine (with sodium bicarb) to force the drug to ionize and allow it to be excreted, not
reabsorbed through the bloodstream.
What is distribution? - How a drug will be transported to the tissues it needs to go to in order for it to
exert its effects
Drug factors related to distribution: - -Lipid solubility
-Molecular size
-Degree of ionization
-Duration of action
-Cellular binding
-Therapeutic effects
-Toxic effects
(lipid soluble, small, and non-ionized drugs will distribute more quickly)
Body factors related to distribution: - -Vascularity (poor perfusion, disruption of blood flow due to
trauma--difficulty distributing)
, -Blood barriers (blood-brain-barrier can be problematic if we need to get drugs to the brain--will need
very high dosing since only a small amount of the drug will get through)
-Transport mechanisms
-Plasma binding proteins
-Disease states
-Volume of distribution
-Drug interactions
What is the key plasma protein involved with protein binding for medications? - Albumin
Why do we monitor albumin? - Indicative of nutritional status and how well protein-bound drugs will be
transported to their target locations
What happens to the therapeutic effect of a drug when the patient is elderly and has very low levels of
albumin? - The drug does not bind to the protein (albumin) as much as expected, so there is a lot of free
drug floating in the plasma; high risk for drug toxicity
Protein bound means: - Inactive form of the drug; does not have any therapeutic effect when bound to a
protein
Free drug means: - Active form of the drug (available for therapeutic effect)
What happens when a patient is on two drugs that are competing for the same protein binding site on the
albumin? - Some drug interactions can occur. Drugs fight for binding position, but both drugs do not get
enough as the usually would. Leads to higher free drug levels, decreased overall albumin binding, and
potential toxicity for both drugs.
**Unpredictable**
What is the 1st pass effect? - PO drug goes through GI tract and absorbs in the stomach or intestines into
local circulation that reaches the liver. The liver inactivates portions of the drug before it goes into
systemic circulation. Some drugs with a very high 1st pass effect may have to be given IV (goes directly
into systemic circulation) or in higher PO doses (watch for side effects)
What is pharmacokinetics? What are its 4 categories? - What the body does to the drug
1. Absorption
2. Metabolism
3. Distribution
4. Excretion
Quickest route of absorption? Slowest? - IV = quickest
IM = slowest
What is the most common way drugs pass through cell membranes? - Passive diffusion
What characteristics of a drug allow it to pass most quickly through cell membranes (usually through
passive diffusion)? - Small, uncharged (unionized), lipid soluble--pass through membrane without any
energy
What does it mean when a drug is ionized? - It means that the drug is stuck in the compartment it was
ionized in and has to be moved to the next compartment (cannot be absorbed into the bloodstream)
Where do weak acids absorb? - Stomach
Where do weak bases absorb? - Small intestine
pH of stomach: - 2-4
pH of small intestine: - 6-7
pH of large intestine: - 6-7
,pH of bloodstream: - 7.35-7.45
pH of bladder: - 5-8
pH of breastmilk: - 7.1
Where will a drug absorb if it is a weak base that ionizes at a pH of 4 and lower? - In the small intestine
(since the stomach has a pH of 2-4, so the drug will become ionized and move to the small intestine
where it will be able to absorb into the bloodstream)
How can we manipulate the urine pH in cases of overdose? - Drugs that are weak acids (aspirin) can be
trapped and excreted through the urine.
We raise pH of the urine (with sodium bicarb) to force the drug to ionize and allow it to be excreted, not
reabsorbed through the bloodstream.
What is distribution? - How a drug will be transported to the tissues it needs to go to in order for it to
exert its effects
Drug factors related to distribution: - -Lipid solubility
-Molecular size
-Degree of ionization
-Duration of action
-Cellular binding
-Therapeutic effects
-Toxic effects
(lipid soluble, small, and non-ionized drugs will distribute more quickly)
Body factors related to distribution: - -Vascularity (poor perfusion, disruption of blood flow due to
trauma--difficulty distributing)
, -Blood barriers (blood-brain-barrier can be problematic if we need to get drugs to the brain--will need
very high dosing since only a small amount of the drug will get through)
-Transport mechanisms
-Plasma binding proteins
-Disease states
-Volume of distribution
-Drug interactions
What is the key plasma protein involved with protein binding for medications? - Albumin
Why do we monitor albumin? - Indicative of nutritional status and how well protein-bound drugs will be
transported to their target locations
What happens to the therapeutic effect of a drug when the patient is elderly and has very low levels of
albumin? - The drug does not bind to the protein (albumin) as much as expected, so there is a lot of free
drug floating in the plasma; high risk for drug toxicity
Protein bound means: - Inactive form of the drug; does not have any therapeutic effect when bound to a
protein
Free drug means: - Active form of the drug (available for therapeutic effect)
What happens when a patient is on two drugs that are competing for the same protein binding site on the
albumin? - Some drug interactions can occur. Drugs fight for binding position, but both drugs do not get
enough as the usually would. Leads to higher free drug levels, decreased overall albumin binding, and
potential toxicity for both drugs.
**Unpredictable**
What is the 1st pass effect? - PO drug goes through GI tract and absorbs in the stomach or intestines into
local circulation that reaches the liver. The liver inactivates portions of the drug before it goes into
systemic circulation. Some drugs with a very high 1st pass effect may have to be given IV (goes directly
into systemic circulation) or in higher PO doses (watch for side effects)
