Introduction To Semisolid Dosage Forms

Question 1

What is the function of human skin?

Answer 1

To protect and keep the outside out and the insides in

Question 2

What are the layers of the skin?

Answer 2

The subcutaneous layer
The dermis layer
The epidermis layer

Question 3

What is the most important layer for the semisolid?

Answer 3

Epidermis → stratum corneum

Question 4

What is the thickness of the inner subcutaneous fatty layer?

Answer 4

Typically several millimeters thick, except for some areas such as the eyelids where it is mostly absent

Question 5

What is the function of the subcutaneous layer of adipose tissue?

Answer 5

Question 6

How thick is the dermis layer?

Answer 6

3 - 5 mm thick

Question 7

What is the dermis layer composed of?

Answer 7

Question 8

How thick is the stratum corneum

Answer 8

Question 9

Where is the stratum corneum thinnest

Answer 9

On the lips and eyelids

Question 10

Where is the stratum corneum thickest

Answer 10

On the load-bearing areas of the body such as the soles of the feat and palms of the hands

Question 11

Semi-solid formulations are selected for what

Answer 11

For increased residence on the skin

Question 12

Transdermal patches are selected for what

Answer 12

For extended drug delivery through the skin

Question 13

Liquid formulations are selected for what

Answer 13

For a rapid short-term input of permeant into the skin

Question 14

What are the principles that guide the selection of a dosage forms and excipient ?

Answer 14

Skin type
Skin cite
Lesion type

Question 15

What are preferred for normal to oily skin ?

Answer 15

Gels

Question 16

What are preferred for normal to dry skin ?

Answer 16

Lotions

Question 17

What are preferred for dry skin ?

Answer 17

Creams

Question 18

What is preferred for hairy areas ?

Answer 18

Lotions
Gels
Sprays

Question 19

What is preferred for intertriginous areas?

Answer 19

Creams and lotions

Question 20

What is preferred for a wet, vesicular, weeping lesion ?

Answer 20

Aqueous based formulation is generally preferred (creams, lotions, gels)

Question 21

What is preferred for a dry, thickened scaly lesion ?

Answer 21

Fatty formulations ( ointments, pastes)

Question 22

Define spreading coefficient

Answer 22

A parameter that measures the ability of one liquid or semisolid to spread over the surface of another

Question 23

How to measure the spread in coefficient

Answer 23

The difference between the work of adhesion and the work of cohesion

Question 24

What does positive S value mean

Answer 24

Work of adhesion is more than the work of cohesion so spreading will occur

Question 25

What does negative S value mean

Answer 25

The work of cohesion is more than the work of adhesion, so spreading will not occur

Question 26

The skin surface has what type of layer?

Answer 26

An aqueous - oily layer

Question 27

What to do to spread the semisolid over the skin

Answer 27

To increase the polarity and eventually the surface coefficient by adding a surfactant

Question 28

What is the importance to study the spreading coefficient in semisolid dosage forms

Answer 28

Patient comfort
Drug efficacy
Cosmetic elegance
Application efficiency

Question 29

What is meant by patient comfort?

Answer 29

Question 30

What is meant by drug efficacy

Answer 30

Question 31

What is meant by cosmetic elegance

Answer 31

Question 32

What is meant by application efficiency

Answer 32