3. 1. SCLERA: protective layer;
maintains the shape of the eye
2. CORNEA: allows light to enter the
eye; powerful refracting surface
3. CHOROIDS: second layer of the
eye and lies between sclera and
retina. Gives nourishment to the
retina
4. IRIS: responds to pupil opening
5. LENS: refract and focus the light
onto the retina
6. RETINA: converts images into
electrical impulse
7. MACULA: located in the center of
the retina. This area has the
sharpest vision
4. Q1. pH of an eye is
1. 2.6
2. 2.8
3. 7.1
4. 9
Q2 The eye lens is
1. Convex
2. Biconvex
3. Concave
4. Biconcave
Q3. Photoreceptors are located:
1. Choroid
2. Sclera
3. Cornea
4. Retina
5. Q4. Vitreous humor is the fluid contained in the anterior segment of the eye?
True or false
Q5. White portion of the eye in humans is
1. Sclera
2. Iris
3. Pupil
4. Retina
Q6. Photoreceptors that detect bright colour called as
1. Rods
2. Cones
7. • They are specialized dosage form that are instilled into the
exterior of the eye(topical), inside(intraocular) or adjacent
(periocular) to the eye
• Must be sterile and same as that of parenteral preparations
• Most commonly used dosage forms: solutions, suspensions &
ointments
• Novel ocular dosage forms: gels, gel forming solutions, ocular
inserts, intravitreal injections, implants
• Commonly used ophthalmic products includes:
1. EYE DROPS
2. EYE LOTIONS
3. EYE OINTMENTS
4. EYE SUSPENSION
5. CONTACT LENS SOLUTION
I
N
T
R
O
D
U
C
T
I
O
N
8. ch
ar
ac
te
ris
tic
s
1. Free from foreign particles: clear, free from any kind of
dust or pathogens. Should be clarified by bacteria proof
filters such as membrane filters, sintered glass filters
2. Sterile: Pseudomonas Aeroginosa (gram-ve)
3. Viscosity: prolong the contact time of the drug in the
eye.eg: Polyvinyl alcohol(1-4%) , PEG, Methyl cellulose
4. Tonicity: should be isotonic with the lacrimal secretions
to avoid discomfort and irritation (0.5-2%NaCl), 1.9%
boric acid
5. pH of the preparation: activity, stability, solubility.
Alkaloid solution is stable at pH 2-3 but this is irritant to
the eye and above 7, they get precipitated
6. Surface activity: preparations should have good
wetting property to penetrate cornea. Eg: benzalkonium
chloride, polysorbate 20, polysorbate 80.
7. Good corneal penetration
8. Simplicity to use the preparations
9. NORMAL pH of tears 7.4 and they itself has some buffer capacity
BUT
ALKALINE pH ACIDIC pH
10. • Drug: antiseptic, anti-inflammatory, mydriatic, miotic properties,
underlying condition.
• Preservatives: should be sterile and should contain
preservatives to avoid microbial contamination. Eg:
benzalkonium chloride(BKL), chlorbutanol, phenylmercuric.
• Sterilization: autoclaving at 121 ºC for 15 minutes or by
bacteria proof filter (0.22um) to avoid thermal degradation
• Isotonicity: NaCl 0.9% and 1.9% boric acid
• Buffer: maintain the pH balance, Eg: boric acid, sodium
phosphate
• Viscosity: methyl cellulose, HPMC
R
E
Q
U
I
R
E
M
E
N
T
S
11. E
Y
E
D
R
O
P
S
Eye drops are sterile aqueous or suspensions of drug that are
instilled in to the eye with a dropper/ without dropper
14. E
Y
E
lo
ti
o
n
• Generally used for washing of the eyes
• Concentrated in nature, sterile water is added before
using
• Iso-osmotic with tears because they causes much more
lacrimal dilution with the fluid
• Sterilized by autoclaving or bacteria proof filters
• Expiry period: 2 days (why?)
15. E
Y
E
oi
nt
m
e
nt
• These are applied to the eye
• Prepared under aseptic conditions and packaged in
collapsible tubes – nowadays, eye applicaps are available
for a single use
16. E
Y
E
su
sp
en
si
on
• They produce longer effect than solutions
• Disadvantage: difficult to ensure that suspension does not
contain large particles
• Prepared only in those cases where the drug is insoluble/
unstable liquid dosage form
17. FACTORS AFFECTING DRUG AVAILABILITY
1. Rapid solution drainage by gravity,
blinking reflex, induced lacrimation
2. Superficial absorption of drug into
conjunctiva and sclera and rapid removal
by the peripheral blood flow
3. Low corneal permeability
Transport of hydrophilic and
macromolecular drugs occurs through
sclera route
Lipophilic agents of low molecular weight
follow trans corneal transport by passive
diffusion
4. Metabolism
5. Min viscosity= 20cp
6.Penetration enhancers: increasing
corneal uptake
18.
19. C
o
nt
ac
t
le
n
s
Made up of PMMA( polymethoxymethylacrylate)
Types: hard and soft lens
For hard lens: two solutions
1.Wetting solution: hydrophobic nature, PMMA is
poorly wetted by lacrimal fluid. Eg: polysorbate 80,
polyvinyl alcohols (may contain traces of acetic
acid)
2.Storage solution: hydrophobic lens tends to attract
hydrophobic substances from the eye lids, fingers
etc. and hence require cleaning after use
For soft lens: they are hydrophilic in nature and
hence require only a single solution.
20. Disadvantages of soft lens:
• Less durable than hard contact lenses.
• Can be dry, especially when using a hair
dryer, in a hot room, or windy and dry
weather, which causes discomfort for some
people.
• Require more treatment
• Vulnerable to protein or fat deposits, that will
reduce the performance of the lens in the
long term
• Can absorb chemicals from the
environment, that can cause eye irritation.
Disadvantages of Hard lens
• Less comfortable at the
beginning of usage.
• Adaptation period takes
longer.
• More sensitive to foreign
objects under the lens, such
as dust.
• Easily released from the eye
• Lens can be scratched and
broken.
21. COMMON EYE DISORDERS
1. Refractive errors: myopic(near-sightedness); hyperopic (far-
sightedness); astigmatism (distorted vision at all distances);
presbyopia
2. Cataract: clouding of the eye’s lens and is the leading cause of
blindness
3. Diabetic retinopathy: It is characterized by progressive damage
to the blood vessels of the retina, the light-sensitive tissue at the
back of the eye that is necessary for good vision
4. Glaucoma: Glaucoma is a group of diseases that can damage
the eye’s optic nerve and result in vision loss and blindness.
5. Amblyopic
27. Q
ua
l
I
ty
co
nt
rol
1. Sterility test
DIRECT INOCULATION MEMBRANE FILTRATION
SOYABEAN-CASEIN
DIGEST MEDIUM:
Incubated at 20-25◦C
FLUID THIOGLYCOLLATE
MEDIUM: Incubated at 30-
35 ◦C on 7 days
30. 4. Metal particles test
10 tubes content in 10 petri dishes
Heat it at 85◦C for 2 hours
Cool it at room temperature to solidify
31. P
A
C
K
A
G
I
N
G
1. PACKAGED IN A PLASTIC BOTTLE: LDPE resin ( cap made of
harder resin than bottle)
Advantages:
Compatible with everything
Disadvantages:
Sorption and permeability issues
LDPE RESIN is translucent.
32. M
A
N
U
F
A
C
T
U
RI
N
G
• Environment should be sterile and
particle free
• Laminar flow should be used
throughout the process
• Relative humidity: 40-60%
• Separate entrance for personnel's
• BLOW/FILL/SEAL METHOD
• Used for manufacturing unpreserved
ophthalmic products