The present invention includes compositions and methods for making and using a rapid dissolving, high potency, substantially amorphous nanostructured aggregate for pulmonary delivery of tacrolimus and a stabilizer matrix comprising, optionally, a polymeric or non-polymeric surfactant, a polymeric or non-polymeric saccharide or both, wherein the aggregate comprises a surface area greater than 5 m2/g as measured by BET analysis and exhibiting supersaturation for at least 0.5 hours when 11-15-times the aqueous crystalline solubility of tacrolimus is added to simulated lung fluid.