Chapter 2: Review of Basic Principles of Pharmacology Flashcards
What is pharmacology?
The study of drugs and their actions.
Pharmacokinetics is:
A) What the drug does to the body
B) The study of genetic attributes of an individual that lead to variable responses to drugs
C) What the body does to the drug
D) The description and analysis of the cost of drug therapy to healthcare systems and society
C. What the body does to the drug
Pharmacogenomics is:
A) What the drug does to the body
B) The study of genetic attributes of an individual that lead to variable responses to drugs
C) What the body does to the drug
D) The description and analysis of the cost of drug therapy to healthcare systems and society
B) The study of the genetic attributes of an individuals that lead to variable responses to drugs
Pharmacoeconomics are:
A) What the drug does to the body
B) The study of genetic attributes of an individual that lead to variable responses to drugs
C) What the body does to the drug
D) The description and analysis of the cost of drug therapy to healthcare systems and society
D) The description and analysis of the cost of drug therapy to healthcare systems and society
Pharmacodynamics are:
A) What the drug does to the body
B) The study of genetic attributes of an individual that lead to variable responses to drugs
C) What the body does to the drug
D) The description and analysis of the cost of drug therapy to healthcare systems and society
A) What the drug does to the body.
What are the four stages of what the body does to the drug?
Absorption
Distribution
Metabolism
Elimination
Rate of absorption determines how soon effects will begin based on:
- Route: IV, IM, PO, topical, rectal, inhaled, etc
- Characteristic of pharmaceutical preparation (e.g. immediate versus extended release).
- Amount of absorption determines intensity of effect: plasma drug levels
- Bioavailability of drug: percentage of administered dose that enters the bloodstream
Where in the body does more oral absorption occur: A) The mouth B) The stomach C) The colon D) The small intestine
D) The small intestine
Most oral absorption occurs in the small intestine (duodenum, jejunum and ileum)
Absorption is:
The movement of a drug from its site of administration into the blood.
What does it mean for a drug to have low bioavailability?
A) A high percentage of administered dose enters the bloodstream
B) A low percentage of administered dose enters the bloodstream
C) The drug was administered incorrectly
D) The drug will have a short half-life
B) A low percentage of administered dose enters the bloodstream
Because the percentage of the administered dose that does enter the bloodstream is called the bioavailability of the dosage form.
Drugs give via parenteral administration are 100% bioavailable because they are administered directly into the bloodstream.
What types of medications do NOT pass through membranes easily? A) Non-ionic (neutral) molecules B) Lipophilic molecules C) Polar molecules D) Small molecules
C) Polar molecules
Neutral, lipophilic and small molecules WILL PASS relatively easily through the plasma membrane.
Medications
MEDICATIONS that do NOT PASS through the plasma membrane easily include: polar molecules, ions, and large molecules
Distribution is:
The movement of drugs throughout the body
Factors affecting distribution include:
- Blood flow
- Lipid/water solubility
- pH (pH changes the charge of drugs depending on the pKa)
- Protein binding (Albumin; Can increase circulation, decrease metabolism and excretion; Needs to be unbound to have effect)
- Transport systems (E.G., p-glycoprotein)
What are the three ways a drug can pass across a cell membrane?
- Through channels and pores
- Via Transport systems (P-glycoprotein)
- Direct penetration of the membrane
What are the two barriers that should be considered with thinking of drug distribution?
- The Blood Brain Barrier (BBB). Capillary endothelial cells are surrounded by a sheath of glial tissue. Is impermeable to water soluble drugs and ionized drugs
- Plancental Barrier (Pregnancy). Lipid membrane that allows passage of drugs by simple diffusion. Smaller molecules cross most easily.
P-glycoprotein (P-gp) does what?
P-gp plays a part in drug distribution:
1) It is a membrane bound transport system which moves drugs from across membranes (Member of ATP binding proteins).
2) Affects the level of substrate available for absorption/elimination (If a P-gp inhibitor is given, P-gp substrate levels will rise)