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Flashcards in Dry eye preparations Deck (92):
1

what is the most general way to improve dry eyes

using ocular lubricants

2

how many % of the total ophthalmic drugs do artificial tears contribute to in the UK

33%

3

why are artificial tears not exactly the same as natural tears

because lots of glands contribute to natural tears which artificial tears can't mimic

4

other than functioning as lubricants, what do some more recent formulations mimic

the electrolyte composition of human tears (e.g.TheraTears®)

5

what are the 3 forms that ocular lubricants are available as and what are they used to treat

- eyedrops
- gels
- ointments

used to treat the discomfort associated with conditions in which the tear film is reduced or unstable

6

what are lubricant eye ointments also used in the treatment of as well as the discomfort associated with conditions in which the tear film is reduced or unstable

the treatment of recurrent corneal erosions

7

what are the majority of dry eye preparations available as and who can they be sold and supplied by

over the counter (P medicines, GSL or CE marked products) and can be sold and supplied by optometrists

8

what are the most commonly used drugs in optometric practice

ocular lubricants

9

what are the 2 foremost objectives in caring for patients with dry eye disease

- to improve the patient’s ocular comfort and quality of life and
- to return the ocular surface and tear film to the normal homeostatic state

10

symptoms can rarely be ____________, they can often be __________ with ocular lubricants

symptoms can rarely be eliminated, they can often be improved with ocular lubricant

11

what did a systematic review conclude about artificial tears

that they improved the condition of the exposed ocular surface in patients with dry eye, based on Rose Bengal staining as the primary outcome measure.
However, there was no statistical difference in the efficacy of the various formulations

12

list 4 limitations that the treatment of dry eye with ocular lubricants has

- Formulation cannot replace complexity of natural tears
- Administered intermittently rather than continuously as with natural tears. Therefore formulated to increase their contact time e.g. mucoadhesive polymers
- Choice of therapy is determined by the severity of the condition (taking into account the lifestyle and dexterity of the patient)
- The presence of preservatives in artificial tears can compromise the ocular surface following prolonged use

13

what is the recommended treatment of ocular lubricants for mild dry eye disease

Artificial tears up to 4x per day

14

what are the recommended treatments of ocular lubricants for moderate dry eye disease

- Unpreserved artificial tears up to 12x per day with lubricating ointment at night
- Tear conservation

15

what are the recommended treatments of ocular lubricants for severe dry eye disease (name 3)

- Immunotherapy e.g. cyclosporin
- Autologous therapy (serum)
- Tear conservation

16

what is the name of the recommended immunotherapy treatment for severe dry eye disease

cyclosporin

17

list the 7 types of formulations that ocular lubricants are available in

- Cellulose esters
- Carbomers
- Polyvinyl alcohol
- Sodium hyaluronate
- Lubricating ointments
- Acetyl cysteine
- Liposomes (liposomal spray)

18

what type of products are ocular lubricants increasingly available stand what does this stand for

- available as CE–marked products
- These are ‘medical devices’ (similar to contact lens solutions) and therefore not regulated by the Medicines Act

19

if a product is a medical device which is CE marked, what are they not regulated by

the medicines act

20

because ocular lubricants are increasingly available as medical devices, what is a limit as a consequence

their availability on NHS prescriptions

21

what advantage do mucoadhesive properties in ocular lubricants have, and what are they available as

- Increased contact time with the ocular surface
as they are more sticky
- available as mucoadhesive viscous gels
- most are polymers (artificial molecules)

22

what are the side affects associated with mucoadhesive viscous gels

- blurring
- sticky lids

23

what is the most commonly prescribed formulation of ocular lubricants and name 4 examples

Cellulose esters
e.g.
- hypromellose
- hydroxyethylcellulose
- methylcellulose
- carboxymethylcellulose

24

which formulation of drugs are viscoelastic polysaccharides

Cellulose esters

25

what is an advantage of the Cellulose ester formulation of ocular lubricants

Good retention time on ocular surface

26

what is a disadvantage of the Cellulose ester formulation of ocular lubricants

Can cause crusting of eyelids mimicking blepharitis

27

what two forms of packaging are the Cellulose ester formulations of ocular lubricants available as

- unit dose preservative free
or
- multi dose

28

which type of ocular lubricant formulation is the cheapest and thus available on the NHS

Cellulose ester

29

which type of molecule are the ocular lubricant formulation, carbomers

Synthetic polymers

30

name 2 advantages of the carbomer formulation of ocular lubricants

- Good retention time on ocular surface
- Good viscosity when eyes open shear thin during blinking

31

what is a disadvantage of the carbomer formulation of ocular lubricants

- Tends to blur vision

32

what causes the viscosity of tears to be decreased

if applying a force when blinking

33

what behaviour does the tear fluid display

non-Newtonian behaviour

34

what are the majority of solutions unaffected by

the shear rate

35

which type of molecule are the ocular lubricant formulation, Polyvinyl alcohol

Synthetic polymers

36

Polyvinyl alcohol formulations have low....

viscosity

37

which type of dry eye is Polyvinyl alcohol ocular lubricant formulations beneficial in

mucin and lipid deficiency dry eye

38

what is a disadvantage of Polyvinyl alcohol ocular lubricant formulations

Short retention time
therefore need to put in more times

39

which formulation of drugs are Mucopolysaccharides

Sodium hyaluronate

40

Sodium hyaluronate is a __________ formulation

Sodium hyaluronate is a vicious formulation

41

what is the advantage of Sodium hyaluronate ocular lubricant formulations

Good retention time on ocular surface (superior to cellulose esters and PVA)

42

what 2 other formulations is the retention time of Sodium hyaluronat superior to

- cellulose esters
and
- Polyvinyl alcohol

43

which ocular lubricant formulation is a natural product, which makes it work well as a ocular lubricant

Sodium hyaluronate

44

what is the disadvantage of the ocular lubricant formulation, Sodium hyaluronate

Tends to blur vision

45

which ocular lubricant formulation blurs vision less than the Cellulose ester formulation

Sodium hyaluronate

46

what form do ophthalmic lubricating ointments come as

Liquid paraffin

47

ophthalmic lubricating ointments have high....

viscosity

48

what does ophthalmic lubricating ointments contribute to

rebuilding the lipid layer

49

what does ophthalmic lubricating ointments melt at

the temperature of ocular tissues

50

what is the advantage of ophthalmic lubricating ointments

long retention time

51

when is ophthalmic lubricating ointments used at its best

when other artificial tears are used during the day and ophthalmic lubricating ointments used at night

52

what is a disadvantage of ophthalmic lubricating ointments

Blurred vision

53

what can be a result of tear modification as a result of dry eye

Mucolytic in filamentary keratitis

54

which formulation of ocular lubricant needs to be used to treat Mucolytic in filamentary keratitis and at what dose

Acetylcysteine 5-10%

55

name an example of Acetylcysteine 5-10% used to treat Mucolytic in filamentary keratitis and which type of medicine is it available as

- Ilube
- available as POM

56

how does the Acetylcysteine 5-10% formulation of ocular lubricant treat Mucolytic in filamentary keratitis

it dissolves mucous filaments by breaking disulphide bonds

57

what sensation is felt when instilling Acetylcysteine 5-10% into the eye

stinging sensation
the cornea feels rough

58

what is the purpose of preservatives in ocular lubricants

to prevent bacterial contamination

59

what is the drawback of preservatives in ocular lubricants

they are toxic to the ocular surface

60

when do preservatives cause more harm/toxicity to the ocular surface

when they are put into the eye lots of times a day to treat a chronic condition

61

what is the most common type of ocular preservative found in ocular lubricants and solutions

Benzylkonium chloride BAK

62

what affect on the eye can 1 drop of Benzylkonium chloride have after 10 minutes

an effect/morphology on the microvilli of the corneal epithelium and on the corneal stroma

63

what affect on the eye can 1 drop of Benzylkonium chloride have after 6 hours

it strips off microvilli of the corneal epithelium and on the corneal stroma

64

how are preservative free ocular lubricants generally packaged as and what implications does this have

- as single dose minims
- this is more expensive

65

what is Benzylkonium chloride BAK taken up by and what consequences does this have

- by soft contact lenses
- and then is released slowly
- exceeding upper safety limits (increases toxicity)

66

what type of contact lenses absorbs greater quantities of Benzylkonium chloride BAK

High-water content lenses
greater than low water content lenses

67

which lenses take up a very small amount of Benzylkonium chloride BAK and what implications do they have

- hard contact lenses
- and then is released slowly
- approaching upper safety limits (increases toxicity)

68

what can tear film concentrations of benzalkonium, such as after eye drop use in the presence of soft contact lenses could result in

adverse effects on the ocular surface

69

what have newer generation ophthalmic preservatives been developed with

reduced ocular toxicity

70

name 4 newer generation ophthalmic preservatives

- Purite
- Sodium perborate
- SofZia
- Polyquaternium

71

what can newer generation preservatives be used with and why

contact lenses
as they're less toxic

72

what happens to the newer generation preservative purite after going into the eye

dissociates into water, oxygen, sodium, and chlorine free radicals

73

what happens to the newer generation preservative Sodium perborate after going into the eye

converts into water and oxygen on instillation

74

what happens to the newer generation preservative SofZia after going into the eye

it is modified into harmless elements on instillation

75

which newer generation preservative is more common in multi dose contact lens care products, and is less toxic than BAK

Polyquaternium

76

name a brand of ocular lubricant that is a multi dose preservative free system and how does it achieve this

Hycosan
by having a valve system in the neck of its bottle

77

what is the advantage to having a multi dose packaging preservative system

it is more cos effective than single use minims

78

other than Hycosan, name 3 other multi dose preservative free systems with its available dose

- Hylotear 0.1% hyaluronate
- Hyloforte 0.2% hyaluronate
- Hyabak 0.15% hyaluronate

79

what impact does a more concentrated dose (%) preservative free multi dose ocular lubricant have

it sticks more to the ocular surface
but then can affect vision

80

what ingredient does the ocular lubricant Systane contain which causes it to increase its viscosity on contact with the ocular surface

hydroxypropyl (HP) guar

81

what is the mechanism of the ocular lubricant Systane to increase its viscosity on contact with the ocular surface based on

the change in pH
Systane is a liquid in the bottle at a pH of 7.0, but when placed in the eye (which has a pH of ~7.4), a chemical reaction occurs

82

how does the ingredient hydroxypropyl (HP) guar in Systane cause it to increase its viscosity on contact with the ocular surface

the HP guar binds to the ocular surface and simultaneously crosslinks with borate ions in the solution, forming a network with a gel-like consistency

83

what is the ocular lubricant liposomal spray and what does it contain

An aqueous suspension of phospholipid-containing liposomes containing hydrogenated phosphatidylcholine

i.e. a lipid in an emulsion

84

what type of dry eye has liposomal sprays been beneficial in

evaporative dry eye

85

how is the liposomal spray formulation used

it is sprayed onto the closed eyelids

86

what is recognised as a key pathogenetic mechanism of dry eye

inflammation

87

which anti inflammatory drug was the first commercially available pharmaceutical therapeutic agent for the treatment of dry eye/keratoconjunctivitis sicca

Restasis - 0.05% cyclosporine ophthalmic emulsion

available in US but not UK

88

how does autologous serum work as a treatment for dry eye

it uses the patients own blood plasma, this is because it is a neutral substance and is very good for the ocular surface

89

why is autologous serum a good dry eye treatment for the ocular surface

it contains serum and anti-bodies

90

what other alternative dry eye treatments are there from ocular lubricants

ingestion Omega-3 and Omega-6 fatty acids

91

where can Omega-6 fatty acids be found

evening primrose oil

92

which fish contains lots of Omega-3 fatty acids

- mackerel
- tuna
- cod liver