drug delivery systems

1. OCULAR DRUG DELIVER SYSTEMS
By
Sai Dhatri Arige
V. V. Institute of Pharmaceutical Sciences
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2. CONTENTS
Introduction
Physiology of eye
Diseases of eye
Ocular drug delivery systems
Advantages of ocular drug delivery systems
Conclusion
References
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3. INTRODUCTION
These ocular drug delivery systems
were mainly developed to treat eye
locally.
The problem with other dosage forms
is eye irritation ( due to drug particle
size &shape).
It mainly leads to the lacrimation.
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4. 4
Physiology of Eye

5. DISEASES OF EYE
Eye is a sensitive sensory organ
which is located on the surface of
the body.
It is easily prone for many injuries
and infections .
Ocular disorders are classified as 2
Types
1 Periocular diseases.
2 Intraocular diseases.
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6. I. PERIOCULAR DISEASES
 Conjuctivitis:- Redness of the eye and
the presence of a foreign body.
It is mainly caused due to acute
infection or allergy.
Bacterial conjuctivitis is the other most
common ocular infection.
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7. Keratitis:-
It is the condition in which patient feel
decreased vision,ocular pain, red eye and
cloudy/opaque cornea.
It is mainly caused due to bacteria, viruses,
fungi, protozoa and parasites.
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8. II. INTRAOCULAR DISEASES
Infection in the inner eye includes
aqueous humor ,iris ,vitreous humor ,
and retina.
These are majorly effects the eye and
also afford the possibility of spread of
infections.
Glaucoma is the common intraocular
disease present in the world.
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9. OCULAR DRUG DELIVERY SYSTEMS
Ideal characteristics of ocular drug
delivery system
 It should not induce a foreign body
sensation or long lasting blurring.
 It must possess more local activity
 It must deliver drug to the right place
 It should be easy for self- administration.

10. OPTHALMIC SOLUTIONS
Viscous solutions and Hydrogels
 Mucoadhesive Formulations
i.Cationic polymers
ii.Anionic polymers
Dispersed system
i.Liposomes
ii.Nanoparticles
Non-erodible ocular insert
Erodible ocular insert
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11. VISCOUS SOLUTIONS & HYDROGELS
The principle involved in the formulation
of viscous solutions and hydrogels is
addition of hydrocolloids to aqueous drug
solutions.
Polymers used in these formulations are
cellulose derivatives carbomers
polysaccharides, polyvinyl alcohol and
polyvinyl pyrrolidone.
Gels permit longer residence time in the
precorneal area than viscous solutions. 11

12. MUCOADHESIVE FORMULATIONS
These are based up on entaglement of non
covalent bonds between polymers and
mucous.
The polymers used in these formulations are
many high molecular weight polymers with
different functional groups like carboxyl,
hydroxyl, aminosulphates which are
capable of forming hydrogen bonds and
they will not crossing biological membrane.
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13. Anionic polymers: Sodium alginate,
Poloxamers, Carbomers, Sodium
Carboxy Methyl Cellulose.
Cationic polymers: Chitosan.
These formulation helps in increasing
the residence time of drug in the eye.
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14. DISPERSED SYSTEMS
 Lipsomes: The potential advantages
achieved with the liposomes are control of
the rate of encapsulated drug and protection
of the drug from the metabolic enzymes
present at the tear corneal epithelium
interface.
Liposomes are vesicles composed of lipid
membrane enclosing an aqueous volume.
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15. NANOPARTICLES
 This approach is considered mainly for the water
soluble drugs. Nanoparticles are particulate drug
delivery systems 10-1000 nm in the size in
which the drug may be dispersed, encapsulated
or absorbed.
 The materials mainly used for the preparation of
ophthalmic nanoparticles are
polyalkylcyanoacrylates.
 The polymers used for the preparation of
ophthalmic nanoparticles are rapidly bio-
degradable.
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16. IMPLANTS
Scleral and vitreal implants are
developed for treatment of
endophthalmitis. Implants made from
polylactide/glycolide polymers can result
in drug release over 5-6 month period
without the need for replacement.
Retisert and intravitreal implants are able
to delivers the drug over a period of six
months. 16

17. ADVANTAGES OF OCULAR DRUG DELIVERY
 Ocular contact time increases.
 Accurate dose is possible.
 Constant and predictable rate of drug
release can be achieved.
 Systematic absorption can be reduced and
side effects can be reduced.
 Shelf life increased
 Better patient compliance
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18. CONCLUSION
The novel advanced delivered systems
offer more protective and effective means
of the therapy for all inaccessible diseases
or syndromes of eyes.
These ocular drug delivery has been
established with controlled loading and
sustained release.
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19. REFERENCES:
 Controlled drug delivery – Concepts and Advances, by
S.P. Vyas and Roop K. Khar.
 Ansel’s Pharmaceutical dosage forms and drug delivery
systems, by Loyd V. Allen, Nicholas G. Popovich and
Howard c. Ansel.
 Advances in Controlled and Novel drug delivery, edited
by N.K. Jain.
 Textbook of Industrial Pharmacy, edited by Shobharani
R. Hiremath.
 Novel drug delivery systems, by Y.W. Chein, published
by Marcel Dekker, volume 50.
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