The present invention relates to novel methods, compositions and kits useful for the treatment of pulmonary diseases such as pulmonary arterial hypertension. In particular, aerosolisable compositions of iloprost are provided which are for use in inhalation therapy. The administration is by inhalation over a short period of time, which is patient-friendly, effective, and well tolerated. Inhalation may, for example, be achieved using an efficient nebulizer based on the vibrating mesh technology.
