A method of preparing a pharmaceutical formulation which is suitable for inhalation, the method comprising: providing a solution comprising a first solvent or mixture of solvents and a poorly water soluble active agent; providing a second solution comprising a second solvent or mixture of solvents and an excipient. The first and second solvents or mixture of solvents are removed by simultaneously drying both solutions in a spray dryer equipped with a three-fluid nozzle to produce particles comprising an active agent and an excipient.