Delivery of submicrometer and nanometer aerosols to the lungs using hygroscopic excipients or dual stream nasal delivery

A method of targeted delivery of an active agent to a region of the respiratory system of a patient in need thereof, comprising

• providing said active agent to said patient as individually aerosolized submicrometer particles or droplets which combine both
• i) said active agent;
• and
• ii) at least one hygroscopic excipient with a hygroscopic parameter iexρex/Mex of at least 7 kmol/m3;
• wherein said active agent and said at least one hygroscopic excipient are present in said individually aerosolized submicrometer particles or droplets in amounts sufficient to cause a predetermined amount of hygroscopic growth of said individually aerosolized submicrometer particles or droplets during passage through airways having natural airway humidity levels of said patient
• wherein said individually aerosolized submicrometer particles or droplets have a growth coefficient iexρex/Mex·vfex+iaaρaa/Maa·vfaa of at least 2.8;
• where
• iex is the molecular dissociation constant of said at least one hygroscopic excipient,
• iaa is the molecular dissociation constant of said active agent,
• ρex is the density of said at least one hygroscopic excipient,
• ρaa is the density of said active agent,
• Mex is the molar mass of said at least one hygroscopic excipient,
• Maa is the molar mass of said active agent,
• vfex is the solute volume fraction of said at least one hygroscopic excipient, and
• vfaa is the solute volume fraction of said active agent;
• wherein said individually aerosolized submicrometer particles or droplets are at least 250 nm in size;
• wherein submicrometer refers to size according to mass median aerodynamic diameter (MMAD);
• and wherein said predetermined amount of hygroscopic growth caused by said amounts of said active agent and said at least one hygroscopic excipient results in said individually aerosolized submicrometer particles or droplets growing to an aerodynamic diameter which reaches or surpasses 2 μm in size.