The document discusses ocular drug delivery systems. It begins by outlining the composition of tear fluid and how drugs administered via the eye are typically absorbed. It then categorizes various ocular drug delivery systems including conventional, vesicular, particulate, and implant-based systems. Specific examples like liposomes, niosomes, ocular inserts and implants are described in further detail. Key advantages and disadvantages of different systems are provided. Testing parameters for ocular thin films are also listed.

1. Submitted by: Pratiksha Srivastava
M.Pharm
(1st year)
Galgotias university

2. Ocular administration of drug is
primarily associated with the need to
treat ophthalmic diseases.
Meant for local therapy and not for
systemic action.
Applied topically to the cornea, or
instilled in the space between the
eyeball and lower eyelid

4.  Water - 98%
 Solid -1.8%
 Organic element – Protein - 0.67%
 Sugar - 0.65%
 NaCl - 0.66%
 Other mineral element sodium, potassium and
ammonia - 0.79%.

5. D R U G IN TEA R FLU ID
Ocular Absorption
(5% of the dose) Systemic Absorption
(50-100% of the dose)
Major Routes:
-Conjuctiva of eye
-Nose
Minor Routes:
-Lacrimal Drainage
-Pharynx
-Aqueous Humor
-Inner Ocular Tissues
Corneal
Route:
-PrimaryRoute.
-SmallLipophilic
Drugs.
Conjunctival
and Sclera
Route:
-SecondaryRoute.
-LargeHydrophilic
Drugs.
Aqueous
Humor
Ocular Tissue Elimination
5

6.  Sterility
 Isotonicity:
 e.g.: 1.9% boric acid, 0.9% NaCl
 Buffer/pH adjustment
 Less drainage tendency
 Minimum protein binding

7. OCULAR DELIVERY
SYSTEMS
CONVENTIONA
L
VESICULAR
CONTROL
RELEASE
PARTICULATE
IMPLANTS
IONTOPHORESIS
DENDRIMER
MICROEMULSION
NANOSUSPENSION
MICRONEEDLE
MUCOADHESIVE
POLYMERS
7
MICROPARTICLES
NANOPARTICLES
LIPOSOMES
NIOSOMES
DISCOMES
CLASSIFICATION OF OCDDS

8.  Drugs which are active at eye or eye surface are widely
administered in the form of Solutions, Emulsion and
Suspension.
 Various properties of eye drops like hydrogen ion
concentration, viscosity and instilled volume can
influence retention of a solution in the eye.
 Less than 5 % of the dose is absorbed after topical
administration into the eye.
 The dose is mostly absorbed to the systemic blood
circulation via the conjunctival and nasal blood vessels.

9. Dosage form Advantages Disadvantages
Solutions 1. Convenience
2. Usually do not interfere
with vision of patient.
1. Rapid precorneal
elimination.
2. Non sustained action.
3. To be Administered at
frequent intervals.
Suspension 1. Patient compliance.
2. Best for drug with slow
dissolution.
3. Longer contact time
1. Drug properties decide
performance loss of both
solutions and suspended
particles.
2. Irritation potential due to
the particle size of the drug.
Emulsion 1. Prolonged release of drug
from vehicle
1. Blurred vision.
2. patient non compliance.

10.  Prolongation of drug contact time with the external
ocular surface can be achieved using ophthalmic
ointment vehicle.
10
Ointment base is
sterilized by heat and
filtered while molten
to remove foreign
particulate matter.
It is then placed into a
sterile steam jacketed to
maintain the ointment in
a molten state and
excipients are added
The entire ointment
may be passed
through a previously
sterilized colloid mill

11.  Advantages:
1. Longer contact time and greater storage stability.
2. Flexibility in drug choice.
3. Improved drug stability.
 Disadvantages:
1. Sticking of eyes lids.
2. Blurred vision.
3. Poor patient compliance.
4. Matting of eyelids.

12.  Liposomes are biocompatible and biodegradable lipid vesicles
made up of natural lipids and about
25 –100 nm in diameter.
 They are having an intimate contact with the corneal and
conjunctival surfaces which is desirable for drugs that are poorly
absorbed, the drugs with low partition coefficient, poor solubility
or those with medium to high molecular weights and thus
increases the probability of ocular drug absorption.
 Vesicle composed of phospholipid bilayer enclosing aqueous
compartment in alternate fashion.
 It is Biodegradable, Non-toxic in nature.

13.  ADVANTAGES
 Drugs delivered intact to
various body tissues.
 Liposomes can be used for
both hydrophilic and
hydrophobic drug.
 Possibility of targeting and
decrease drug toxicity.
 The size, charge and other
characteristics can be
altered according to drug
and desired tissue.
DISADVANTAGES
They need many
modification for drug delivery
to special organs.
Stability problem and
oxidative degradation.
Requires special packaging
and storing facility.
Costly.

14.  They are non toxic and do not require special handling techniques:
• Niosomes are nonionic surfactant vesicles that have potential
applications in the delivery of hydrophobic or amphiphilic
drugs.
• Discomes act as potential drug delivery carriers as they released
drug in a sustained manner at the ocular site.

15.  The vesicles can act as a depot to release the drug slowly and
offer a controlled release.
 They are osmotically active and stable.
 They increase the stability of the entrapped drug.
 Improves therapeutic performance of the drug by protecting it
from the biological environment and restricting effects to target
cells, thereby reducing the clearance of the drug.

16. OCULAR
INSERTS
NONERODABLE
OCUSERT
SOFT CONTACT
LENSES
ERODABLE
SODI
COLLAGEN SHIELDS
16

17. OCUSERT:
 The Ocusert therapeutic system is a flat, flexible, elliptical
device designed to be placed in the inferior cul-de-sac between
the sclera and the eyelid and to release Pilocarpine continuously
at a steady rate for 7 days.
 The device consists of 3 layers.
1. Outer layer - ethylene vinyl acetate copolymer layer.
2. Inner Core - Pilocarpine gelled with alginate main polymer.
3. A retaining ring - of EVA impregnated with titanium dioxide.

19. • ADVANTAGES
 Reduced local side effects and toxicity.
 Around the clock control of drug.
 Improved compliance.
• DISADVANTAGES
 Retention in the eye for the full 7 days.
 Periodical check of unit.
 Replacement of contaminated unit
 Expensive.

20.  Contact lenses can be a way of providing extended
release of drugs into the eye.
 Conventional hydrogel soft contact lenses have the ability
to absorb some drugs and release them into the post lens
lachrymal fluid, minimizing clearance through the
conjunctiva.
 Their ability to be a drug reservoir strongly depends on
the water content and thickness of the lens, the
molecular weight of the drug, the concentration of the
drug loading solution and the time the lens remains in it.

21.  The solid inserts absorb the aqueous tear fluid and
gradually erode or disintegrate. The drug is slowly
leached from the hydrophilic matrix.
 They quickly lose their solid integrity and are
squeezed out of the eye with eye movement and
blinking.
 Do not have to be removed at the end of their use.

22.  LACRISERTS
 Sterile rod shaped device made up of hydroxyl propyl
cellulose without any preservative.
 For the treatment of dry eye syndromes.
 It weighs 5 mg and measures 1.27 mm in diameter
with a length of 3.5 mm.
 It is inserted into the inferior fornix.
 SODI
 Soluble ocular drug inserts.
 Small oval wafer.
 Sterile thin film of oval shape.
 Weighs 15-16 mg.
 Use – glaucoma.
Lacriserts

23.  Minidisc
 Countered disc with a convex front and a concave back surface.
 Diameter – 4 to 5 mm.
 Composition
 Silicone based prepolymer (4-methacryloxy)-butyl poly di methyl
siloxane. (M2DX)
 M-Methyl a cryloxy butyl functionalities.
 D – Di methyl siloxane functionalities.
 Pilocarpine, chloramphenicol.

24. Type Advantages Disadvantages
Erodible
inserts
Effective.
Flexiblility in drug
type & dissolution rate.
Need only be
introduced into eye &
not removed.
Patient discomfort.
Requires patient
insertion.
Non-erodible
inserts
Controlled rate of
release.
Prolonged delivery.
Flexibility for type of
drug selected.
Sustained release.
Patient discomfort.
Irritation to eye.
Tissue fibrosis.
Advantages And Disadvantages Of
Ocular Inserts

25.  1. Implants
1. Implants have been widely employed to extend the
release of drugs in ocular fluids and tissues particularly in
the posterior segment.
2. Implants can be broadly classified into two categories
based on their degradation properties:
(1) Biodegradable
(2) Nonbiodegradable
Implants can be solids, semisolids or particulate-based
delivery systems.

26.  For chronic ocular diseases like cytomegalo virus (CMV)
retinitis, implants are effective drug delivery system. Earlier non
biodegradable polymers were used but they needed surgical
procedures for insertion and removal.
 Presently biodegradable polymers such as Poly Lactic Acid
(PLA) are safe and effective to deliver drugs in the vitreous
cavity and show no toxic signs.

27. . Thickness of film
2. Content uniformity
3. Uniformity of Weight
4. Percentage moisture absorption
5. Percentage moisture loss
6. In-vitro drug release
7. In-vivo drug release
8. Accelerated stability studies