1.2 Ointment

Question 1

Definition of ointment

Answer 1

A viscous, homogenous, semisolid preparation intended for external as well as topical application on a variety of body surfaces

Question 2

Where is the application of ointment ?

Answer 2

Skin and the mucous membranes

Question 3

Uses of ointments

Answer 3

Emollients or for the application of active ingredients to the skin for protective, therapeutic, or prophylactic purposes

Question 4

3 classifications of ointments

Answer 4

1. Based on their composition and physical characteristics related to bases
   -oleaginous bases
   -absorption bases
   -water-removable bases
   -water-soluble bases
2. Based on water solubility
   -hydrophobic ointment
   -hydrophilic ointment
   -water-emulsifying ointment
3. Based on therapeutic activity and penetration to skin
   -epidermic ointment
   -endodermic ointment
   -diadermic ointment

Question 5

4 Types of bases

Answer 5

-water-soluble base
-emulsion base
-absorption base
-oleaginous base

Question 6

What are the properties of water-soluble base ?

Answer 6

-absorb and dissolve in water
-washable
-non-greasy
-Don’t deteriorate
-support mold growth

Question 7

What are the advantages of water-soluble base ?

Answer 7

-wide range of compatibility
-non-irritating
-don’t support microbial growth
-easily washed off

Question 8

Disadvantages of water-soluble base ?

Answer 8

gradual discoloration with certain drugs

Question 9

Give the examples of emulsion base properties

Answer 9

-miscible with water
-contain o/w emulgents
-can be easily removed

Question 10

Based on the nature surfactant present, emulsion bases are divided by three and give examples :

Answer 10

-anionic emulsion bases (eg: hydrophilic and emulsifying ointment)
-cationic emulsion bases (eg: cetrimide emulsifying ointment)
-non-ionic emulsion bases (eg: cetomacrogol emulsifying wax)

Question 11

What are the advantages and disadvantages of emulsion base ?

Answer 11

Advantages:
-washable
-non-greasy

Disadvantages:
-subject to water loss if o/w
-greasy
-unwashable
-subject to mopd growth

Question 12

Properties of absorption base ?

Answer 12

-non-emulsified (absorb water and aqueous solutions to produce w/o emulsions)
-w/o emulsions ( absorbing more water)

Question 13

Advantages and disadvantages of absorption base ?

Answer 13

Advantages:
-highly compatible
-relatively stable to heat
-can be used in anhydrous form

Disadvantages:
-greasy
-less occlusive

Question 14

What are the properties of oleaginous base ?

Answer 14

-anhydrous
-don’t absorb water readily
-insoluble in water
-not washable

Question 15

Advantages and disadvantages of oleaginous base ?

Answer 15

Advantages:
-highly compatible
-occlusive
-Good emollients

Disadvantages:
-difficult to remove from skin and clothing

Question 16

Selection of appropriate base based on physicochemical factors

Answer 16

-easy removable
-release rate of drug substance
-stability of drug in ointment
-topical or percutaneous absorption
-effect of drug on ointment base

Question 17

Selection of appropriate base based on patient factors

Answer 17

-if a patient’s skin is dry, occlusive ointment base that retains moisture is recommended

Question 18

Properties that affect the choice of an ointment base

Answer 18

-stability
-penetrability
-solvent property
-irritant effects
-ease of application and removal

Question 19

What are the requirements of ointments ?

Answer 19

1. Microbial content
   -Don’t need to be sterile
   -meet FDA requirements of the test absence of bacteria “s.areus/p.aeruginosa”
2. Minimum fill
   -packaging
   -storage
   -labelling
   -additional: viscosity

Question 20

Method of preparing ointments

Answer 20

-trituration/ incorporation
-fusion
-chemical reaction
-emulsification

Question 21

Explain the trituration method

Answer 21

-a finely insoluble medicaments distributed by grinding with a small amount of base
-fine powders are placed in a mortar or on a ointment
-gently mixed with base until mixture is homogenous
-if liquid ingredients present, before incorporate liquid ingredients, a portion of base is placed on the ointment slabbed a recess made to hold the liquid
-ointment is transferred to the container

Question 22

Explain fusion method

Answer 22

-ointment base contains a number of solid ingredients like white bees wax, acetyl alcohol, steady alcohol and hard paraffin
-all or some of the components of ointment combined and melted together and cooled with constant stirring until congealed
-heat-liable Substances and any volatile components are added last when the temperature of the mixture is low enough

Question 23

How do ointments packaged ?

Answer 23

-suitable plastic tubes or syringes
-ointment jars

Question 24

Storage and containers for ointments

Answer 24

-store in a cool place but don’t freeze
-shelf life 4 weeks
-screw-capped amber glass
-plastic pots
-collapsible metal tubes

Question 25

What is a levitating agent ?

Answer 25

-Mineral oil for oily bases or bases wher3 oil are external phase. -Levigating agent should be equal in volume to the solid material