Preparation and Characterization of Instantly-soluble Solid Eye Drop for Glaucomatous Patients

For the treatment of glaucoma eye drops are chronically used. However, chronic use of preservatives in eye drops cause irritation problem and aff ects ocular tissues. The aim is to formulate an instant soluble solid eye drop to avoid using preservatives since solid dosage forms do not require preservation. Ocular mini-tablets of dorzolamide hydrochloride (DZ) and timolol maleate (TM) were prepared by direct compression using diff erent polymers and were evaluated for their physical properties. The release DZ and TM was compared to COSOPT eye drops. Formulation F2 mini-tablets (which contain DZ, TM, mannitol and microcrystalline cellulose MCC) were chosen as the optimum formula because they had uniform shape and minimum variation in weight 9.69 ± 0.55 mg. Thickness and diameter were 1.38 ± 1.28 and 3.01 ± 0.03 mm, respectively, within the acceptable limits. Hardness and friability were also within the permissable range which were 4.14 ± 0.22 kg/cm2 for hardness and 0.73% ± 0.05 for friability. The drug content for both DZ and TM were within the acceptable limits and the release had no signifi cant diff erence (p > 0.05) compared to commercial eye drop and the mini-tablets dissolved completely with less than one minute. The FTIR and DSC revealed no interaction between the drugs and excipients used. Sterilization using gamma radiation was performed to test the animal’s mini-tablets. The radiation did not signifi cantly (p > 0.05) alter any properties of F2 and no signs of irritation on the animal eye appeared. In conclusion, instant soluble solid eye drop in the form of mini-tablet was successfully prepared by direct compression method and caused no irritation when tested on animals