· Suramine: discovered in 1921, it is used in treatment of the initial phase of T.b. rhodesiense. There are certain undesirable effects, especially on the digestive tract.
· Pentamidine: discovered in 1941, it is used in treatment of the initial phase of T.b. gambiense sleeping sickness. In spite of a few undesirable effects, it is well tolerated by patients. Future production is guaranteed by an agreement between WHO and Aventis.