Hydrophilic Ointment

1K.S.Rathore * 2R.K.Nema, 3S.S.Sisodia, 3M.S.Ranawat

1B. N. Girls College of Pharmacy, Udaipur

2Rishiraj College of Pharmacy, Indore

3B.N. College of Pharmacy, Udaipur

Eye is unique and very precious organ. It is considered the window of the soul. We can enjoy and toured the world, alone with that body. There are many eye diseases that affect this organ, and can be loss of eye sight too. Therefore, many systems ophthalmic drug delivery are available. These are classified systems.Most conventional and new drug delivery formulations commonly available ophthalmic drops and ointments. But these preparations when they are injected into the cul-de-sac are rapidly cleared from the eye cavity due to the tear flow and tear runny nose. Only a small amount is available for its therapeutic effect resulting from dosing1 frequent. Thus, administration of drugs ineffective in the eye is due to the rapid return tear, tear. drainage and dilution of drug tears2.

The local administration for ocular therapeutics is ideal because of small doses required in relation to systemic use, its rapid onset of action and lack of systemic toxicity, topical ocular drug must penetrate the interior of the transcorneal eye and penetration is believed to be the main route for drug absorption. absorption of the cornea is much slower than disposal. For many drugs loss of K (elimination rate of first order) is about 0.5-0.7/min and K absorption (absorption rate of the first order) is about 0001 / min. The sum of these two rate constants control the fraction of applied dose absorbed by the eye3. Thus, the ocular bioavailability can be increased by decreasing or increasing K IOSSA absorption K. The former can be achieved by modifying the dosage forms and eye it in formulating dosage forms containing eye lipophilic prodrugs or adding penetration enhancers. Therefore, to optimize topical drug delivery system eye long contact time with the surface of the cornea and better penetration through the cornea is necessary4.

A considerable amount of effort has been made in the administration of ophthalmic drugs since the 1970s. The two main approqches are trying to improve the bioavailability and controlled delivery of drug release.

IMPROVEMENT of bioavailability

            Topical bioavailability can be improved by optimizing the absorption of drugs and minimizing precorneal drug precorneal losses.

1. Improving the viscosity:

To prolong the precorneal residence time and improve the bioavailability of attempts have been made to increase the viscosity of the formulation. The viscosity enhancers have been used hydrophilic polymers such as cellulose, sugar alcohol and polyacrylic acid. cellulose sodium carboxy methyl is one of the most important polymers having mucoadhesive mono strength5 accession. The effects of polyacrylic acid and polyacrylamide hydrogels are tested on basic miotic
pilocarpine response. Carbomer were used in liquid and semi-solids such as suspending or viscosity agents increases. Formulations including creams, gels and ointments have been used as ophthalmic products6. Polycarbophil is insoluble in water using crosslinked polyacrylic acid in maintaining the system of delivering medicines in eye7 due to the bonding hydrogel and the mucoadhesive strength. Hyaluronic acid provides a biodegradable and biocompatible matrix for the manufacture of sustained-release forms eye-dosage form based on esters of hyaluronic acid benzyl was used for sustained release ophthalmic methylprednisolone. Films and microspheres were also prepared from hyaluronic acid. polysaccharide xanthan gum as has been seen an increase in viscosity8. Today, the hydrophilic polymers continue to be used in the formulation of ophthat.