Interpolymeric complexes (IPCs) have the advantage of combined properties of their constituent polymers. They are easy to prepare under mild conditions and do not require high processing costs. The interpolymeric complexes of alginate, chitosan and Nystatin, as antifungal drug systems, represent an alternative for mucosal illness treatment. The composition of the two polymers is a key parameter in obtaining the desired properties for pharmaceutical formulations. IPCs of sodium alginate (SA) and chitosan (CS) were prepared via solution mixing method with various compositions, followed by coacervation in 2-propanol. The outcome obtained from rheological measurements was that the complex SA/CS 60/40 (v/v %) fulfilled the requirements of a semi-solid formulation, e.g. pseudoplasticity. Nystatin showed very good compatibility with the polymeric system. The drug loaded gels showed better rheological, textural and mechanical properties (e.g. pseudoelasticity, spreadability, surface adhesion etc.). The final gel formulations showed no cytotoxic effects in the cell culture assay.