Ivacaftor is a medication used to treat certain types of cystic fibrosis, a genetic disorder that affects the lungs and digestive system. It works by enhancing the function of a specific protein called CFTR that is defective in people with this condition. By improving the movement of salt and water in and out of cells, ivacaftor helps to reduce the thick mucus that can cause breathing difficulties. This drug is typically prescribed for patients aged 6 months and older who have specific mutations in the CFTR gene. It is taken orally, usually twice a day, and is often used in combination with other therapies to manage symptoms and improve overall lung function.