Pharm principles random

Question 1

Irreversible Comp. inhibitors effect on Km

Answer 1

Unchanged

Question 2

Pharmacokinetics vs Pharmacodynamics

Answer 2

PK - what body does to drug

PD - what drug does to body

Question 3

Vd =

Answer 3

amount of drug in body / plasma drug concentration

Question 4

Decreased protein binding of drug…

Answer 4

Increases Vd (less trapped in plasma)

Question 5

Clearance (CL) =

Answer 5

rate of elimination of drug / plasma drug concentration

= Vd x Ke (elimination constant)

Question 6

t(1/2) =

Answer 6

0.693 x Vd / CL

Question 7

Half-lives vs. SS%

Answer 7

1 - 50%
2 - 25%
3 - 12.5%
3.3 - 10%
4 - 6.25%

Question 8

Loading does =

Answer 8

Cp x Vd / F

Question 9

Maintenance dose =

Answer 9

Cp x CL x dosage interval (time b/t dose) / F

Question 10

Does time to SS change with DOSE or DOSING FREQ?

Answer 10

NO (but concentration at SS may change)

Question 11

Intramuscular or subcutaneous have greater absorption rate?

Answer 11

Intramuscular - d/t high vascularity

Question 12

Zero order elimination drugs?

Answer 12

Phenytoin, Ethanol, Aspirin (high concentrations)

Question 13

Weak acids and OD Rx

Answer 13

Phenobarbital, methotrexate, aspirin, TCAs

Rx Bicarbonate

Question 14

Weak bases and OD Rx

Answer 14

Amphetamines

Rx ammonium chloride, VitC/Cranberry juice

Question 15

Phase 1 metabolism

Answer 15

@ ER: reduction, oxidation, hydrolysis w/ cytochrome P-450

Question 16

Phase 2 metabolism

Answer 16

@ cytosol: conjugation (Glucuronidation, Acetylation, Sulfation)

Question 17

Location of CYP450 drug metabolism

Answer 17

Liver AND Gut

Question 18

Therapeutic index =

Answer 18

Median toxic dose (TD50) / Median effective dose (ED50)

Question 19

Low TI Drugs

Answer 19

Digoxin, Lithium, Theophylline, Warfarin

Question 20

High TI indicates…

Answer 20

Selectivity

Question 21

Jimson Weed (Datura)

Answer 21

Atropine-like (gardener’s pupil)

Question 22

Atropine flush

Answer 22

High dose antimuscarinic causes cutaneous VD (unknown mechanism)

Question 23

Tetrodotoxin

Answer 23

bind fast voltage-gated Na+ channels in cardiac and nerve tissue (blocks AP w/out changing RMP)

Question 24

Ciguatoxin

Answer 24

Opens Na channels causing depolarization

- Temp-related dysesthesia

Question 25

Scombroid

Answer 25

Bacterial histidine decarboxylase converts histidine to histamine (not degraded by cooking)

Question 26

Saxitoxin

Answer 26

From dinoflagellates in “red tide”

- VG-Na channel blocker