The approved dosing regimen for iloprost is 6 to 9 times daily (no more than every 2 hours) during waking hours, according to individual need and tolerability. The significant clinical effects observed in the pivotal study of patients with PAH were achieved with a median dose of 30 μg per day (range: 12.5 to 45 μg delivered at the mouthpiece), corresponding to 6 daily inhalations of 5 μg. The majority of patients (> 80%) in the pivotal study used this median dose or a higher dose with an excellent treatment compliance after 12 weeks.