摘要 |
Embodiments of the invention relate to particles of active substances, methods for preparing the particles, formulations containing the particles, and metered dose inhalers containing the particles or formulations. In one embodiment, an inhaler contains an aerosol formulation containing a particulate active substance of non-micronized, solid particles having a mass median aerodynamic diameter of less than 10 μm. The particles may be suspended in a nonsolvent hydrofluorocarbon fluid vehicle (e.g., HFA 134a or 227ea) at a concentration within a range from about 0.2% w/v to about 5% w/v. The formulation exhibits a flocculation volume of about 85% or greater about 1 minute after mixing the particulate active substance and the vehicle. The particulate active substance may contain salmeterol xinafoate, budesonide, salbutamol sulfate, dihydroergotamine mesylate, risperidone-(9-hydroxy)-palmitate, bromocriptine mesylate, or derivatives thereof. In some examples, the active substance is dihydroergotamine mesylate. |