Abstract: Compositions, methods and kits to be used as a lubricant and for treatment of a cavity pathology including joint pathology are provided. The composition comprises therapeutically effective amounts of at least one bioactive agent, such as magnesium compound, at least one lubricating agent, such as hyaluronic acid, and at least one cell membrane repairing agent, such as polyethylene glycol. The components of these compositions may be administered by a direct application, an application through a cannula, an intra-articular injection, as a flush fluid during an arthroscopy of the affected area, as a post-arthroscopy injection, or as part of a lavage of the area affected by the intra-articular pathology. In addition, the composition of the present invention may be administered to the patient from a pump or a depot.