A method for introducing an organic drilling fluid additive into an aqueous drilling fluid in a subterranean formation, where the method includes introducing loaded microparticles into an aqueous drilling fluid. The loaded microparticles are made by absorbing at least one organic drilling fluid additive onto hybrid calcium carbonate microparticles to form loaded microparticles. The method further includes delivering the drilling fluid into a subterranean formation, and optionally shearing the loaded microparticles to release the absorbed drilling fluid additive(s) into the drilling fluid, such as by shearing them at the drill bit.