{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:38:49Z","timestamp":1792791529914,"version":"4.5.0"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,4,15]],"date-time":"2025-04-15T00:00:00Z","timestamp":1744675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Western Balkans Mobility Scheme\u2014A POLICY ANSWERS Pilot Program","award":["101058873"],"award-info":[{"award-number":["101058873"]}]},{"name":"Western Balkans Mobility Scheme\u2014A POLICY ANSWERS Pilot Program","award":["451-03-136\/2025-03\/200161"],"award-info":[{"award-number":["451-03-136\/2025-03\/200161"]}]},{"name":"Western Balkans Mobility Scheme\u2014A POLICY ANSWERS Pilot Program","award":["451-03-137\/2025-03\/200161"],"award-info":[{"award-number":["451-03-137\/2025-03\/200161"]}]},{"name":"Ministry of Science, Technological Development and Innovation, Republic of Serbia","award":["101058873"],"award-info":[{"award-number":["101058873"]}]},{"name":"Ministry of Science, Technological Development and Innovation, Republic of Serbia","award":["451-03-136\/2025-03\/200161"],"award-info":[{"award-number":["451-03-136\/2025-03\/200161"]}]},{"name":"Ministry of Science, Technological Development and Innovation, Republic of Serbia","award":["451-03-137\/2025-03\/200161"],"award-info":[{"award-number":["451-03-137\/2025-03\/200161"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Background: The incorporation of polymers into drug delivery vehicles has been shown to be an effective strategy to prolong the residence time of active ingredients in the precorneal tear film and to increase ocular bioavailability. Objectives: The aim of this study was to develop novel, viscous eye drops containing olopatadine (OCH) as the active ingredient, polysaccharides hydroxypropyl guar gum (HPG), and sodium hyaluronate (SH), individually, and in combination as functional polymers. Methods: Viscous eye drops containing 0.1% OCH in combination with HPG (0.25%) and SH (0.4%), were prepared and evaluated for their physicochemical properties, rheological behavior, mucoadhesion, and preliminary stability. A novel rheological method was used to evaluate the resistance of the eye drops under simulated blinking conditions. In vivo efficacy was evaluated using an ocular itch test in mice to compare the formulations with a commercial product. Results: The formulations remained stable and transparent, with physicochemical parameters within acceptable ranges. Rheological studies confirmed pseudoplastic flow, with the HPG-SH combination exhibiting enhanced viscosity and shear-thinning properties for prolonged retention in the eye. Mucoadhesion was highest in SH-HPG formulations. During simulated blinking cycles, eye drops containing a combination of SH and HPG polymers fully regained their initial viscosity during the resting periods. Preliminary stability studies indicate that the formulated eye drops exhibit satisfactory physicochemical stability under various storage conditions. In vivo, OCH-SH and OCH-HPG-SH drops provided prolonged antipruritic and analgesic effects compared to the reference product. Conclusions: Polysaccharide-based innovative formulations improve OCH retention, enhancing therapeutic efficacy and patient compliance in the treatment of allergic conjunctivitis.<\/jats:p>","DOI":"10.3390\/pharmaceutics17040517","type":"journal-article","created":{"date-parts":[[2025,4,15]],"date-time":"2025-04-15T06:50:27Z","timestamp":1744699827000},"page":"517","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Stability and Efficacy of Mucoadhesive Eye Drops Containing Olopatadine HCl: Physicochemical, Functional, and Preclinical In Vivo Assessment"],"prefix":"10.3390","volume":"17","author":[{"given":"An\u0111elka","family":"Ra\u010di\u0107","sequence":"first","affiliation":[{"name":"Department of Pharmacy, Faculty of Medicine, University of Banja Luka, Save Mrkalja 14, 78000 Banja Luka, Bosnia and Herzegovina"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4685-483X","authenticated-orcid":false,"given":"Veljko","family":"Krstono\u0161i\u0107","sequence":"additional","affiliation":[{"name":"Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Hajduk Veljkova 3, 21000 Novi Sad, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Micov","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, University of Belgrade\u2014Faculty of Pharmacy, Vojvode Stepe 450, 11221 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2732-5978","authenticated-orcid":false,"given":"Uro\u0161","family":"Pecikoza","sequence":"additional","affiliation":[{"name":"Department of Pharmacology, University of Belgrade\u2014Faculty of Pharmacy, Vojvode Stepe 450, 11221 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5086-9017","authenticated-orcid":false,"given":"Vladimir","family":"Dobri\u010di\u0107","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, University of Belgrade\u2014Faculty of Pharmacy, Vojvode Stepe 450, 11221 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erna","family":"Turkovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Technology and Cosmetology, University of Belgrade\u2014Faculty of Pharmacy, Vojvode Stepe 450, 11221 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5525-0109","authenticated-orcid":false,"given":"Danina","family":"Kraji\u0161nik","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Technology and Cosmetology, University of Belgrade\u2014Faculty of Pharmacy, Vojvode Stepe 450, 11221 Belgrade, Serbia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1007\/s11882-024-01150-0","article-title":"Allergic conjunctivitis management: Update on ophthalmic solutions","volume":"24","author":"Leonardi","year":"2024","journal-title":"Curr. 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