This article deals with the comprehension of the rheological mechanisms relevant to drill in fluid invasion through reservoir rocks, aiming the design of a solids free non-invasive fluid. The strategy to develop this concept was to flow different kinds of fluids (Newtonian and different polymeric solutions) through consolidated inert porous media. Experimental results indicate that Newtonian fluids, CMC solutions and low concentration XC and PHPA solutions were properly fit by Darcy law. On the other hand, the highly concentrated solution presented relevant deviations. Such deviations tended to increase with the increase of deformation rate (or differential pressure). This fact indicates that there is a need for applying viscoelastic constitutive models to account for the extra friction losses. An expression for resistive force estimation as function of the first normal stress difference correlated properly with the experimental results.