About Papain A fruit-derived cysteine protease enzyme present in papaya, Dietary supplement, a digestive aid. Indications for Papain 1.Improve blood circulation 2.Prevent abnormal blood clotting. 3.Reduce pain and inflammation associated with Phlebitis. 4.Alleviate the pain, inflammation, and discomfort of varicose veins. 5.Minimize muscle pain that occurs after exercise.