Iloprost is primarily used in the treatment of pulmonary arterial hypertension (PAH) to improve symptoms and exercise capacity by dilating blood vessels and reducing blood pressure in the lungs. It is also employed in managing severe frostbite to promote blood flow and prevent tissue damage. Additionally, iloprost is utilized in Raynaud's phenomenon to alleviate symptoms by improving circulation in the extremities. Its vasodilatory and antiplatelet properties make it effective in various vascular conditions.