IRCT20110811007297N8 IRCT 2022-05-22 Shiraz University of Medical Sciences Efficacy and Safety of Ophthalmic Probiotic Lysate on Ocular Surface of Patients With Dry Eye Syndrome Efficacy and Safety of Ophthalmic Probiotic Lysate on Ocular Surface Microbiota, Immunological and Clinical Outcomes of Patients With Dry Eye Syndrome 2022-05-22 anticipated 40 Complete https://irct.ir/trial/57030 interventional Randomization: Randomized, Blinding: Triple blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment, Randomization description: Simple randomization list will be generated by Excel software. Each eye will be randomly assigned to the active drug or placebo according to the randomization list, Blinding description: Blinding of the patients will be achieved by the similarity of drug and placebo. Blinding of the outcome assessor will be achieved by not disclosing patients allocation group to the assessor. Blinding of the statistician will be achieved by not disclosing data groups to him. 2 Dry eye syndrome. Intervention 1: Intervention group: ophthalmic probiotic drop, 1 drop Q6h, for 4 weeks. Intervention 2: Control group: ophthalmic placebo drop, 1 drop Q6h, for 4 weeks. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is It is not yet known if there will be a plan to make this available