Cinchona is used for increasing appetite, promoting the release of digestive juices, and treating bloating, fullness and other digestive complaints. It is also used for blood vessel disorders including haemorrhoids, varicose veins and leg cramps. Some people use cinchona for the common cold and fever. As a culinary herb, cinchona is used a bitter flavouring in tonic water and alcoholic beverages. Cinchona bark also contains quinine, a medicine used to treat malaria.