Pharm: Basic Principles

Question 0

Plasma proteins which bind basic protein

Answer 0

Orosomucoid

Question 1

A few drugs are enzymes themselves like ___ which metabolizes uric acid

Answer 1

Pegloticase

Question 2

Excretion of amphetamine is facilitated by acidifying/alkalinizing urine? How about aspirin?

Answer 2

Excretion of a weak base such as amphetamine is faster in acidic urine. Excretion faster in weak acid such as ASA in alkaline urine.

Question 3

Is retinoic acid for acne given as a topical preparation or a transdermal preparation?

Answer 3

Topical. Topical route includes application to skin or to mucous memorable of the eye, ear, nose, throat, airway or vagina for local effect. Transdermal route involves application to skin for systemic effect.

Question 4

This parameter relates the amount of drug in the body to the concentration in the plasma

Answer 4

Volume of distribution

Question 5

The concentrations of these three drugs decrease in a linear fashion over time

Answer 5

Zero order kinetics

Ethanol
Phenytoin
Aspirin

Question 6

Identify which type of antagonism exists.

1. Pralidoxime + malathion
2. Secretin + gastrin
3. Atenolol + dobutamine

Answer 6

1. Chemical
2. Physiologic
3. Pharmacologic

Question 7

T/F. The higher the therapeutic index, the safer the drug

Answer 7

True. Therapeutic index is the ratio of the TD50 to the ED50. A safe drug is expected to have a very large toxic dose and a much smaller effective dose.

Question 8

Most common type of drug receptors in the body

Answer 8

G-protein coupled receptors

Question 9

This describes the time required for the amount of drug in the body or blood to fall by 50%. For drugs eliminated by ____ kinetics, this number is a constant regardless of the concentration.

Answer 9

Half-life.

First-order kinetics

Question 10

A 100 kg man takes in wonder drug X, a drug which is completely retained in the plasma compartment. In this instance, what is the volume of distribution.

Answer 10

4L.
Vd is equal to the plasma volume if the drug is completely retained in the plasma compartment. Plasma volume is about 4% of body weight.

Question 11

What is the formula for half-life

Answer 11

(0.693 x Vd) / Cl

Question 12

Quinacrine is a drug avidly bound in peripheral tissues. Do we expect the Vd of the drug to be greater or lesser than the physical body volume?

Answer 12

Greater. Drug would have a low plasma drug concentration.

Vd = (Amount in the body) / (plasma concentration)

Question 13

How many half-lives of dosing at a constant rate are considered adequate to produce the effect to be expected at steady state?

Answer 13

3 - 4 half lives

Question 14

What is the formula for maintenance dose? Loading dose?

Answer 14

Maintenance dose =
( Cl x desired concentration ) /
Bioavailability

Loading dose formula as above but change Cl to Vd

Question 15

T/F. The therapeutic window is the safe range between the maximum therapeutic concentration and the minimum toxic concentration.

Answer 15

F. It is the difference between the MINIMUM therapeutic and toxic concentrations.

Question 16

Inducers of CYP3A4 enzymes

Answer 16

Phenytoin
Carbamazepine
Corticosteroids
Efavirenz
Pioglitazone
Rifampin
Barbiturates

Question 17

Inhibitors of CYP3A4

Answer 17

Amiodarone
Azoles
Cimetidine
Clarithromycin
Cyclosporine
Erythromycin
FQs
Grapefruit
Protease inhibitors
Metronidazole
Quinine
Tacrolimus
SSRI

Question 18

Amine drugs that undergo N-acetylation

Answer 18

HIP
Hydralazine
Isoniazid
Procainamide

Question 19

Inhibitors of intestinal P-glycoprotein

Answer 19

Verapamil
Grapefruit
Mibefradil

Question 20

Drugs normally expelled by intestinal p-glycoprotein

Answer 20

Digoxin
Cyclosporine
Saquinavir

Question 21

In vivo test for mutagenicity? In vitro?

Answer 21

Ames test is an in vitro test; dominant lethal test is an in vivo test.

Question 22

Identify which phase of the clinical trial is described.

1. Involves 100-200 patients with the disease in question.
2. Determines whether the agent has the desired efficacy
3. Pharmacokinetics of the drug is studied
4. Rare toxicities hopefully identified
5. Study benefits and toxicities of the drug under conditions of proposed clinical use

Answer 22

1. Phase 2
2. Phase 2
3. Phase 1
4. Phase 4
5. Phase 3