Dry powders comprise a cannabinoid, a polymer binding agent, a dispersing agent, and a bulking agent, and optionally an antioxidant, and are formed by carbon dioxide-assisted nebulization and drying in a flowing dry stream of gas. The dry powders have an aerodynamic particle distribution effective for delivery by respiration into the lungs of a patient. Methods of preparing a dry powder comprise subjecting a solution of a volatile component, a cannabinoid, a polymer binding agent, a dispersing agent, and a bulking agent, and optionally an antioxidant, to carbon dioxide-assisted nebulization, and drying droplets formed by the nebulization in a flowing dry gas stream to form a dry powder. The dry powder has an aerodynamic particle distribution effective for delivery of the dry powder by respiration into a lung of a patient and/or exhibit increased bioavailability and/or storage stability of a cannabinoid. The dry powder can be compressed into a wafer.
