Deck 4: Drug Absorption and Dissolution: Understanding Mechanisms and Factors

Question 1

A drug can be absorbed by more than one mechanism.

A)True
B)False
C)none
D)all

Answer 1

True

Question 2

Which kind of absorption mechanism is showing in the picture?

A)Endocytosis
B)Passive transport
C)Active transport
D)Facilitated diffusion

Answer 2

Passive transport

Question 3

Which one of these is a physicochemical property of Drug substance?

A)Drug solubility
B)Disintegration time
C)Age of patient
D)Dissolution time

Answer 3

Drug solubility

Question 4

Which one of these does not come under a physicochemical property of drugs?

A)Drug solubility
B)Disintegration time
C)Dissolution rate
D)Drug stability

Question 5

In the sequence of events in the drug absorption from orally administered solid dosage, which one comes at first?

A)Disintegration
B)Disaggregation
C)Dissolution
D)Absorption

Question 6

Which one is the correct sequence for drug absorption through the oral route?

A)Absorption - Dissolution - Disintegration - Deaggregation
B)Disintegration - Dissolution - Deaggregation - Absorption
C)Disintegration - Deaggregation - Dissolution - Absorption
D)Disintegration - Deaggregation - Absorption - Dissolution

Question 7

Patient-related factors of drug absorption do not deal with which one of these?

A)Age
B)Gastric Emptying time
C)Intestinal transit time
D)Pharmaceutic ingredients

Question 8

The rate at which drug reaches the systemic circulation is determined by the slowest of the various steps involved in the sequence. This is known as ____________

A)Disintegration time
B)Dissolution time
C)Rate limiting step
D)Gastric Emptying time

Question 9

Diffusion coefficient of drug D, Greater the value faster us the dissolution.

A)True
B)False
C)none
D)all

Question 10

Greater the surface area lesser is the dissolution.

A)True
B)False
C)none
D)all

Question 11

Which one of the following is a critical rate-limiting step of drug absorption?

A)Rate of drug disintegration
B)Size of the drug
C)Size of the porous particle
D)Rate of dissolution

Question 12

Which sentence will define the Dissolution rate?

A)Amount of solid substrate that goes into solution under constant time
B)Amount of solid substrate that goes into solution under constant time under standard temperature
C)Amount of solid substrate that goes into solution under constant time under standard temperature, pH, and pressure
D)Amount of solid substrate that goes into solution under constant time under standard temperature, pH, solvent composition and constant surface area

Question 13

What should be the ideal solubility rate of an orally administered drug in the pH range of 2 to 8?

A)3-4mg/ml
B)4-6 mg/ml
C)7-8 mg/ml
D)1-2 mg/ml

Question 14

Which one of these is not a theory of Drug dissolution?

A)Diffusion layer model
B)Fick's law of diffusion
C)Penetration or surface renewal theory
D)Interfacial barrier model

Question 15

Which theory takes into account that a thin film is created by the solution of the solid at the solidliquid interface?

A)Interfacial barrier model
B)Diffusion layer model
C)Penetration or surface renewal theory
D)Danckwert's model

Question 16

In the equation G=Ki (Cs-Cb), what does G stands for______________

A)Dissolution rate per unit area
B)Effective interfacial transport constant
C)Concentration of the solute
D)Concentration of the impurity

Question 17

Which model does not approve the existence of the stagnant layer in the solid-liquid interface?

A)Interfacial barrier model
B)Diffusion layer model
C)Penetration or surface renewal theory
D)Danckwert's model

Question 18

What does the interfacial barrier model states?

A)An intermediate concentration exists at the interface
B)Turbulence in the dissolution medium exists at the solid/liquid interface
C)Formation a thin film or layer at the solid-liquid interface
D)Solutes passes easily through the interfaces

Question 19

In the equation, Wo1/3-W1/3=Kt, K stands for ____________

A)The original mass of the drug
B)Mass of the drug remaining after time t
C)Dissolution constant
D)Concentration of solute

Question 20

Which are the two rate-determining step of drug absorption when given orally?

A)Disintegration and deaggregation
B)Disintegration and Dissolution
C)Dissolution and permeation through the membrane
D)Permeation through the membrane and Disintegration

Question 21

The maximum amount of solute dissolved in a given solvent under standard conditions of temperature, pressure, and pH is known as __________

A)Dissolution rate
B)Intrinsic dissolution
C)Rate limiting step
D)Absolute or intrinsic solubility

Question 22

In the equation, V dC/dt = dm/dt = A(Cs-Cb).? ? D, what does ? stands for?

A)Mass of the solid dissolved
B)Rate of surface renewal
C)Concentration of solute
D)Concentration of the drug

Question 23

Each face of the crystal has a different interfacial barrier.

A)True
B)False
C)none
D)all

Question 24

Absorption of drugs can be categorized into 2 classes, physicochemical properties of drugs and Dosage form of the drug, on the basis of drug dissolution.

A)True
B)False
C)none
D)all

Question 25

Which option will be the best example of the physicochemical properties of drugs?

A)Solubility, particle size, polymorphism, salt form, pseudo polymorphism, complexation, wettability, pH, Pressure of disintegration
B)Pressure of disintegration, polymorphism, salt form, pseudo polymorphism, complexation, wettability, pH
C)Solubility, particle size, polymorphism, salt form
D)Solubility, particle size, polymorphism, salt form, pseudo polymorphism, complexation, wettability