Semisolid Dose Forms

Question 1

what are 3 dose forms that are considered semisolid dose forms?

Answer 1

ointments
creams
gels

Question 2

what are these dose forms mainly intended for? what other uses do they have?

Answer 2

topical application

ophthalmic, nasal, vaginal, or rectal use

Question 3

what must you consider when making topical products?

Answer 3

systemic drug absorption if the patient is pregnant or nursing

Question 4

why do you have to consider systemic drug absorption for pregnant/nursing women?

Answer 4

drugs can enter the fetal blood supply and breast milk and be transferred to the fetus/nursing infant

Question 5

what are ointments?

Answer 5

semisolid preparations intended for external application to the skin or mucous membranes and they may or may not be medicated

Question 6

what are non-medicated ointments used for?

Answer 6

their protective, emollient or lubricating activity

Question 7

what are ointment bases used for?

Answer 7

for their physical effects or as vehicles in medicated ointments

Question 8

what are the 4 groups of ointment bases?

Answer 8

oleaginous bases
absorption bases
water-removable bases
water-soluble bases

Question 9

what is the use of oleaginous bases?

Answer 9

have an emollient effect on the skin, protect against the escape of moisture and are effective as occlusive dressings
they remain on the skin for a long time

Question 10

why are oleaginous bases hard to wash off?

Answer 10

they are immiscible in water

Question 11

can you incorporate aqueous or water solutions with oleaginous bases?

Answer 11

ye, but only in small quantities and with difficulty

Question 12

what levigating agent could be used to incorporate powders into oleaginous bases?

Answer 12

liquid petrolatum (mineral oil)

Question 13

what are 2 examples of oleaginous bases?

Answer 13

white petrolatum USP

vaseline

Question 14

what are absorption bases?

Answer 14

essentially water in oil emulsions

Question 15

what are the two types of absorption bases? give an example of each

Answer 15

1) those that allow incorporation of water to form an emulsion (w/o)
ex: hydrophilic petrolatum
2) those that are already emulsions (w/o)
ex: lanolin

Question 16

what is the use of absorption bases? (2pts)

Answer 16

provide a way of incorporating small volumes of aqueous solutions into hydrocarbon (oleaginous) bases
can be used as emollients, though not as occlusive as oleaginous bases

Question 17

how do you incorporate aqueous solution into oleaginous bases?

Answer 17

incorporate the aqueous solution into the absorption base, and then incorporate this mixture into the hydrocarbon base

Question 18

what are 2 examples of absorption bases?

Answer 18

cold cream

Nivea

Question 19

what are water-removable bases?

Answer 19

essentially oil in water emulsions, easily removed from the skin by washing and can be diluted with aqueous solutions

Question 20

what are some examples of water-removable bases?

Answer 20

hydrophilic ointment USP
dermabase
unibase

Question 21

what makes water-soluble bases different from the other ointment bases?

Answer 21

do not contain and oleaginous components so they are completely water washable and often referred to as greaseless

Question 22

what are water-soluble bases used for? why?

Answer 22

incorporation of solid materials as the addition of water/aqueous solutions will dissolve then and they lose their semisolid consistency

Question 23

what is an example of a water-soluble base?

Answer 23

polyethylene glycol ointment NF

Question 24

what are the considerations for choosing an appropriate base? (11pts)

Answer 24

1) water content
2) water affinity
3) spreadability
4) washability
5) drug incorporation
6) drug release
7) occlusive?
8) absorbed topically or percutaneous
9) stability of drug in base
10) effects of drug on product consistency
11) site of application

Question 25

what is the water content for each of the ointment bases?

Answer 25

ole - anhydrous abs - hydrous rem - hydrous sol - anhydrous/hydrous

Question 26

what is the water affinity for each of the ointment bases?

Answer 26

ole - hydrophobic abs - intermediate rem - hydrophilic sol - hydrophilic

Question 27

what is the spreadability for each of the ointment bases?

Answer 27

ole - difficult abs - moderate rem - easy sol - moderate/easy

Question 28

what is the washability for each of the ointment bases?

Answer 28

ole - no washability abs - poor washability rem - washable sol - washable

Question 29

what is the drug incorporation for each of the ointment bases?

Answer 29

ole - solids/oils abs - solids/oils/some aqueous rem - solids/aqueous sol - solids/aqueous

Question 30

what is the drug release for each of the ointment bases?

Answer 30

ole - poor abs - intermediate rem - fair sol - good

Question 31

which of the ointment bases show occlusive properties?

Answer 31

oleaginous base absorption base (intermediate) water-removable/water-soluble are not occlusive

Question 32

what are the two main methods of preparing an ointment?

Answer 32

incorporation | fusion

Question 33

which method is more commonly used for ointment preparation: trituration or spatulation?

Answer 33

spatulation

Question 34

what must you do with solids before you incorporate them into the base? why?

Answer 34

reduce particle size so the product will not be gritty

Question 35

if you were to levigate the solid that is to be added to the base, what are some requirements for the levigating agent?

Answer 35

chemically/physically compatible with the drug and base

Question 36

what levigating agent is best used for bases where the external phase is oil? external phase is water?

Answer 36

oil - mineral oil | water - glycerin

Question 37

what method to reduce particle size would you use for camphor (gummy material)?

Answer 37

pulverization by intervention

Question 38

what is pulverization by intervention?

Answer 38

the material is dissolved in a solvent (like alcohol) and spread out on the slab and allowed to dry as a thin film. you can then work it into other ingredients by spatulation

Question 39

what tools do you use for preparing an ointment on a glass slab?

Answer 39

broad-bladed stainless steel spatula and a smaller version to periodically remove accumulated material from the larger

Question 40

when would you use plastic spatulas instead of metal ones?

Answer 40

when a component may react with the metal (ex iodine)

Question 41

what would you use for incorporation of liquids/solutions of drugs: a mortar/pestle or a glass slab? why?

Answer 41

mortar and pestle because the liquid is more captive than on a glass slab

Question 42

what two things need to be taken into consideration when mixing the ointment base with a liquid?

Answer 42

1) base is compatible with the liquid | 2) make sure the volume added is not too large, causing the product to become too semi-liquid

Question 43

how does the fusion method work?

Answer 43

some or all of the components are melted together and cooled with stirring until congealed

Question 44

what product components work for fusion and not for incorporation?

Answer 44

products containing: beeswax stearyl alcohol high MW polyethylene glycols (PEGs)

Question 45

In what order are the materials melted?

Answer 45

start with the material of highest melting point, then move to the material with the next highest melting point

Question 46

why do we add materials in order based on MP?

Answer 46

a lower temp is sufficient to achieve fusion since the first melted components exert a solvent effect on the successive materials

Question 47

what is usually the highest temp needed for fusion?

Answer 47

70°C

Question 48

what kind of substances must you treat with caution when using the fusion method?

Answer 48

volatile and heat liable substances

Question 49

why do you use a water bath for fusion?

Answer 49

to avoid excessive heating

Question 50

what should you do if you're fusing an aqueous and oleaginous mixture?

Answer 50

both should be heated separately then combined with stirring | add the aqueous to the oleaginous

Question 51

what are creams?

Answer 51

semisolid preparations containing medication dispersed in an emulsion base and after application, the water evaporates leaving a film of the oleaginous components

Question 52

what makes creams more cosmetically acceptable?

Answer 52

less greasy and easier to spread/remove

Question 53

when is an ointment preferable over a cream?

Answer 53

occlusive action is preferred and the skin is dry/scaly

Question 54

when do you use creams rather than ointments?

Answer 54

when the skin is weeping or there are exudates | creams tend to be drying

Question 55

what 2 forms can lotions be found in? what are they typically formulated as?

Answer 55

fine suspensions emulsions formulated as semi-liquid creams

Question 56

what are pastes?

Answer 56

thick, stiff preparations usually with a high content of solid material often to the order of 25%

Question 57

what are pastes used for?

Answer 57

absorb serous secretions and as protectants

Question 58

what is an example of a paste being used as a protectant?

Answer 58

zinc oxide paste used to treat diaper rash

Question 59

what are plasters/glycerogelatins?

Answer 59

archaic products designed for long-term application to the skin

Question 60

what is the difference between plasters and glycerogelatins?

Answer 60

plasters - have backing of paper/fabric glycerogelatins - plastic masses which are heated before use to melt them then paint onto skin where they solidify, then covered with a bandage

Question 61

give an example of a plaster

Answer 61

corn plaster | contains salicylic acid that is used for corn removal

Question 62

what have glycerogelatins been used to treat?

Answer 62

varicose ulcers

Question 63

what are topical dermatological products usually packaged in?

Answer 63

jars or tubes

Question 64

what are rectal, vaginal, and ophthalmic products usually packaged in?

Answer 64

tubes

Question 65

describe what ointment jars typically look like/are made of

Answer 65

made of glass or plastic | wide mouths with screw caps

Question 66

what are tubes typically made of?

Answer 66

aluminum (lined with plastic) | plastic

Question 67

what is the typical size range for ointment jars?

Answer 67

15-500mL

Question 68

what is the typical size range for tubes?

Answer 68

3-120mL

Question 69

what is included with tubes for rectal/vaginal use?

Answer 69

applicator tip

Question 70

how are the jars filled?

Answer 70

air entrapment is avoided product does not touch lid pack weighted product into jar using spatula (unless made via fusion, then pour)

Question 71

how do you package tubes?

Answer 71

weighed material may be rolled in a tube of suitable paper, the roll is inserted into the open end of the tube, then the paper is withdrawn while flattening holding down the edge of the tube crimp end of tube to seal it