Ms. RIFFAT YASMIN

Objectives Discuss types of Ophthalmic Dosage forms with examples Interpret the Advantages & Disadvantages of : 1. Ophthalmic solutions a) Ophthalmic Gel forming solutions b) Powders for Ophthalmic solutions 2. Ophthalmic Suspension 3. Ophthalmic Ointment 4. Ophthalmic Emulsion 5. Ophthalmic Gels 6. Ophthalmic Inserts 2

Ophthalmic solutions Advantages: Ingredients are completely dissolved, inexpensive manufacturing, accepted standard of care. Disadvantages: Messy, compliance issues, short residence time, dilution and washout, require high drug concentration, systemic side-effects *A thickening agent may be used to increase the viscosity but there is a chance to develop residue in the eyelashes. 3

Ophthalmic Gel-forming solutions These are aqueous solutions of polymer having low viscosity that forms a gel in contact with the tear protein, pH change, temperature change. Advantages: Ingredients are completely dissolved. Adequate contact time of medicament with the eye Disadvantages: It may develop residue in the eyelashes. 4

Powders for solutions Due to least instability of the drug in an aqueous solvent some ophthalmic products are available in dry powder form that requires reconstitution by the pharmacist prior administration. Instruction: Aseptic environment is required for reconstitution to maintain efficacy of the product. 5

Ophthalmic Suspensions These are aqueous suspensions of one or more medicament. Advantages: Adequate contact time of medicament. Increased duration of action. Disadvantages: It may develop residue in the eyelashes. 6

Ophthalmic Ointment These are anhydrous, containing Liquid paraffin, Wool fat and Yellow soft paraffin in the proportions 1:1:8. They are used for therapeutic and diagnostic purposes and contain drug such as Antimicrobial, Corticosteroid & NSAIDs, Advantages: Having increase contact time Good bioavailability Disadvantage: Interfere with vision (they are mostly used at bed time i.e. HS) 7

Ophthalmic Emulsion It mostly comprised of water & castor oil (as oily phase) Advantages: Possesses the ability to deliver the poor water soluble drug in solublized form as eye drops. O/W emulsion is less irritant to the eye. Increase contact time Good bioavailability Disadvantage: W/O emulsion may interfere with vision 8

Ophthalmic Gel In the making of ophthalmic gels, Carbomer (polymer) is used in aqueous medium. Advantages: Significantly increased contact time Increased drug bioavailability Decreased dosage frequency Disadvantages: Blurred vision due to increased water content 9

Ocular Insert Ocuserts are the new drug delivery systems which are designed in such a way that they release the drug at predetermined and predictable rates thus eliminating the frequent administration of the drug. A drug-dispensing ocular insert containing a drug and suited for application to the eyeball, stay over a prolonged period of time, but the inserts must then be removed when they are no longer needed. 10

Contd. The systems generally include controlled, delayed and or sustained release. e.g. The Pilocarpine inserts used in glaucoma therapy PILOCAR-20, PILOCAR

12 THANK YOU

Reference: Ansel’s: Pharmaceutical Dosage Forms & Drug Delivery Systems (8 th Ed): by Howard C. Ansel Chapter: 17 Pharmaceutical Practice: by D.M Collette Chapter: 28 Remington: The Science & Practice of Pharmacy 13