Pharmacy – drugs/pharmacokinetics – metabolism/excretion/absorption/distribution/routes of admin/ type of reactions/polypharmacy/variability due to other factors – eg age/pregnancy.

Question 1

What is pharmacology?

Answer 1

the science that broadly deals with the physical and chemical properties, action, absorption, and fates of chemical substances termed drugs that modify biological function
- pharmakon = drug

Question 2

Who is considered the Father of Chinese Medicine? What did he write?

Answer 2

Emporer Shen-Nung

Pen Tsao - list of herbal remedies considered the earliest compilation of drugs

Question 3

What is Kahun Papyrus?

Answer 3

most ancient document on gynaecology

Question 4

Who is considered the father of medicine?

Answer 4

Hippocrates, who conducted systemic observations of his patients’ symptoms

Question 5

What is the Pharmacopoeia?

Answer 5

official compilations of medicinal substances, their preparations, use, and dosages

Question 6

What fueled the founding of the first veterinary colleges and hospitals?

Answer 6

response to epidemics of diseases, such as rinderpest

Question 7

What are the 3 branches of pharmacology?

Answer 7

Pharmacokinetics (PK) - study of the 4 key physiological processes that govern the time course of drug fate: Absorption, Distribution, Metabolism, Excretion - what the body does to the drugs.

Pharmacodynamics (PD) - study of cell/tissue responses and selective receptor affect - what drugs do to the body.

Pharmacogenetics (PG) - study of genetic determinants of response to drug therapy

Question 8

What is a drug?

Answer 8

a molecule that interacts with specific molecular components of an organism to produce biochemical and physiologic changes/effects

(any chemical that can affect living processes)

Question 9

What are the 3 major ways drugs are classified based on source?

Answer 9

ORGANIC DRUGS: plants (digoxin, morphine, penicillin), animal (insulin, oxytocin)

INORGANIC DRUGS: minerals (iron, calcium)

SYNTHETIC DRUGS: most common

Question 10

What are the 3 major ways drugs are classified based on chemical structure?

Answer 10

STEROIDS: derived from cholesterol (sex hormones, cortisol)

GLYCOSIDES: (digoxin, digitoxin)

BARBITURATES: derived from barbituric acid

Question 11

What are the 3 major ways drugs are classified based on biological effects?

Answer 11

CARDIAC IONOTROPES: increase cardiac contractility (benazepril)

NEUROMUSCULAR BLOCKERS: block transmission between a nerve muscle fiber

ANTIMICROBIALS: bacteriostatic and bacteriocidal drugs

Question 12

In what 3 ways can drugs be named?

Answer 12

CHEMICAL NAME: IUPAC-given name that describes the drug using chemical nomenclature.

GENERIC NAME (nonproprietary): shortened name originating during drug development.

TRADE/BRAND NAME (proprietary): commercial name used for marketing - simple, catchy

Question 13

What is the purpose of drug therapy?

Answer 13

Induce a desired pharmacologic response

Question 14

How is the degree of pharmacologic response controlled?

Answer 14

presence of drug concentration at the tissue (receptor)

Question 15

What processes regulate the absorption, distribution, and excretion of drugs in an animal?

Answer 15

Processes that govern the movement of drugs across lipid-based biological membranes

Question 16

What are the 4 ways that drugs move through the body?

Answer 16

bulk flow*

passive diffusion*

carrier-mediated transport

endocytosis / pinocytosis

Question 17

What is bulk flow?

Answer 17

movement across the fenestrated capillaries of the body from plasma to tissue

Question 18

What is the most common molecular weight of drugs?

Answer 18

< 350

Question 19

What is bulk flow dependent on? What is it independent of?

Answer 19

the concentration of drug dissolved in the plasma or tissue fluid (higher concentration = higher diffusion)

chemical nature of the of the drug

Question 20

What is passive diffusion? What 5 things is it dependent on?

Answer 20

drug movement across cell membranes (transmembrane diffusion)

lipid solubility
environmental pH
surface area
thickness of the membrane to be transversed
concentration of diffusible drug

Question 21

What is the most common method by which compounds move through the body?

Answer 21

passive diffusion

Question 22

What are the 2 major characteristics of drugs that affect their solubility?

Answer 22

molecular weight

partition coeficient (PC)

Question 23

What is the partition coefficient of a drug? What does a high number indicate?

Answer 23

The ratio determined by mixing the drug in a combination of water and an organic solvent (relative oil vs water affinity of a compound when it exists in its unionized form)

greater distribution, high lipid solubility, and greater ability of a drug to pass through the cell membrane

Question 24

According to pH, how are most drugs characterized?

Answer 24

Most drugs are either weak acids or weak bases

Question 25

What is pKa?

Answer 25

pH at which 50% of the drug exists in the ionized state and 50% in the nonionized, lipid soluble state

Question 26

How does the environmental (host) pH affect a drug’s passive diffusion?

Answer 26

drugs will be more nonionized and more likely to diffuse into tissues when in a “like” environment (pH = pKa)

drugs will be trapped by ionization when present in an “unlike” environment

Question 27

How does drug absorption differ in the stomach and gut (intestine)?

Answer 27

STOMACH: weak acids are better absorbed in the acidic environment

GUT: weak bases are better absorbed in the alkaline environment

Question 28

What is the Hendersen-Hasselbalch equation?

Answer 28

equation used to calculate the percentage ionized of a drug or determine the concentration of a drug across a biological membrane

Question 29

What is carrier-mediated transport?

Answer 29

type of a diffusion where pH partitioning does not apply, and specialized membranes have specific carriers/transport systems/receptors

(can be active of passive)

Question 30

What are the 2 types of carrier-mediated transport?

Answer 30

1. Facilitated diffusion-passive transport (NO ATP) using a carrier protein to bind the drug and carry it across the membrane along with the concentration gradient
2. Active transport - using a specific carrier protein that uses ATP to move a drug across the membrane against the concentration gradient

Question 31

What are the main 2 things that carrier-mediated transport is dependent on? Why is this system used?

Answer 31

specificity and saturability

drugs normally cannot cross the membrane by passive diffusion because they are not lipophilic, so they need transporters

Question 32

In what 4 instances is carrier-mediated transport important?

Answer 32

1. GI absorption of essential nutrients and drugs (beta-lactams)
2. cellular uptake (glucose)
3. removal of drugs from the CSF
4. biliary and renal excretion of drugs

Question 33

What are 3 examples of facilitated diffusion?

Answer 33

1. reabsorption of glucose by the kidney
2. absorption of vitamin B12 from the intestine
3. ion channels

Question 34

How can active transport be used after absorption?

Answer 34

Removal of a drug after it has been absorbed (excretion/removal)

Question 35

What is the active transporter, P-glycoprotein?

Answer 35

AKA multidrug resistance protein, MDR1

ATP-driven efflux transporter encoded by MDR1/ABCB1, and highly expressed at the BBB, BTB, kidney, liver, intesting, and placenta to keep exogenous compounds out of critical tissues (Collies and Ivermectin)

Question 36

What is endocytosis/pinocytosis?

Answer 36

a compound binds to the surface of the membrane and the membrane invaginates and interiorized the compound

(not common of transmembrane passage for most drugs)

Question 37

Weak bases are better absorbed in what condition?

Answer 37

alkaline conditions