Lecture 12C - Topical Administration (Other locations)

Question 1

What formulation is used for nails?

Answer 1

solid formulations such as a nail lacquer

Question 2

What is the structure of the nail?

Answer 2

hard keratinised structure

delivery through the nail plate is challenging

Question 3

What is needed to increase diffusion of the drug through the nail plate?

Answer 3

keratolytic components such as urea

Question 4

Example of nail treatment?

Answer 4

amorolifine (nail fungal infection)

Question 5

What do keratolytic components do?

Answer 5

make the nail more porous and allows the delivery if the drug through the nail plate

Question 6

What is the barrier to drug absorption in the eye?

Answer 6

caused by physiological and biochemical mechanisms (tears and blinking)

Question 7

What must formulations applied to the eye be?

Answer 7

sterile

Question 8

Most common formulation used in the eyes?

Answer 8

solutions (eye drops)

90% of ocular formulations

Question 9

Advantages of eye drops?

Answer 9

easy to administer

homogenous (better dose uniformity)

Question 10

Disadvantages of eye drops?

Answer 10

rapidly drained out of the eye (even with the presence of viscosity enhancers)

lack of efficacy

Question 11

Example of a viscosity enhancer?

Answer 11

polyvinylalcohol

Question 12

How long are eye drops retained in the eye?

Answer 12

90% elimination after 30 seconds

Question 13

How much of a dose of eyedrops reaches the aqueous humour (site of action)?

Answer 13

1-5% of the instilled dose

Question 14

Examples of eye drops?

Answer 14

chloramphenicol, ciprofloxacin (corneal ulcers)

Question 15

Ointments for eyes?

Answer 15

mainly used of lipophilic excipients (petrolatum, lanolin)

Question 16

Advantages of eye ointments?

Answer 16

reduce drug drainage caused by tear flow

increase of corneal residence time
sustained drug release (2-4h)
incorporation of drugs with poor aqueous solubility

Question 17

Disadvantages of eye ointments?

Answer 17

more difficult to administer

more variable administered dose

blurring of vision (reduction in patient compliance)

Question 18

Examples of eye ointments?

Answer 18

chloramphenicol, ciprofloxacin (corneal ulcers)

Question 19

Administration to the ear?

Answer 19

solutions (ear drops)

Question 20

Advantages of ear drops?

Answer 20

same as for eye drops

Question 21

Formulation of ear drops?

Answer 21

viscous formulations (by adding glycerol, PEG)

increase of residence time of the formulation and prolonged contact with area of infection

Question 22

Examples of ear drops?

Answer 22

chloramphenicol, clotrimazole for the treatment of ear infection (otitis)

Question 23

Administration to the nose?

Answer 23

creams and ointments

removal of the drug from the nasal cavity

Question 24

What do formulations administered to the nose need?

Answer 24

increasing nasal residence time by bioadhesion, increase formulation viscosity

ointments and creams

Question 25

Examples of nose formulation?

Answer 25

mupirocin, chlorhexidine, neomycine (eradication of staphylococci)

Question 26

Oropharyngeal administration?

Answer 26

solutions, gels, suspensions, mucoadhesive buccal tablets

Question 27

What do suspensions do?

Answer 27

deposit antimicrobial drug on the mucosa surface, which improves the residence time of the drug but dissolution needed prior permeation

Question 28

Examples of oropharyngeal administration?

Answer 28

miconazole gel and mucoadhesive tablets (fungal infections such as thrush, candidiasis)

nystatin suspension (fungal)

chlorhexidine mouthwash

Question 29

Vaginal administration?

Answer 29

gels, creams, pessaries, ovules

Question 30

What are pessaries?

Answer 30

vaginal suppository

solid, single dose formulations, of ovoid shape

Question 31

What are ovules?

Answer 31

vaginal capsules, shell pessaries

solid, single dose formulations similar to an oral soft capsule, but their shape is often elongated

larger size ovoid

Question 32

Advantages of vaginal administration?

Answer 32

treatment of local infections with a much lower dose than with oral administration

no need of absorption of the drugs for local action

Question 33

Disadvantages of vaginal administration?

Answer 33

release of the drug is influenced by varying volumes of vaginal fluids

Question 34

Examples of vaginal administration?

Answer 34

clotrimazole (cream, pessary)

antifungal miconazole (ovule)

metronidazole (gel)

Question 35

What is glycerol?

Answer 35

helps to increase the residence time of ear drops

Question 36

What is lanolin?

Answer 36

can be used to formulate eye ointments

Question 37

What is urea?

Answer 37

keratolytic, which helps increase diffusion of drug through the nail plate

Question 38

What is polyvinylalcohol?

Answer 38

viscosity enhancer, which helps to reduce the elimination of eye drops