Composition (A) for killing trypanosomes and blood schizonts, for human or veterinary use, comprising pentamidine (I) and pyremethamine (II), metronidazole (III) or tinidazole (IV) as active ingredients, is new.

A pharmaceutical preparation having trypanocidal and blood schizontocidal activity, for use in human or veterinary medicine, contains as active agents (A) pentamidine and (B) pyremethamine, metronidazole or tinidazole. The presence of pentamidine is not essential if the preparation additionally contains nisin