The investigation of plant mixtures used in traditional medicine in Northern Peru yielded a total of 974 herbal preparations used to treat 164 different afflictions. Psychosomatic disorders were, with almost 30% of all recipes applied, the most important afflictions treated. In most cases, healers used only one or two mixtures to treat an illness. However, up to 49 different preparations were used to treat the same disease. This indicates a high degree of experimentation. Altogether 330 plant species, representing almost 65% of the medicinal flora used in the region were applied in mixtures. The overwhelming number of plant mixtures contained 2-7 different plant species, although in the most extreme case 27 distinct species were included. The cluster analysis confirmed that mixtures used for applications like inflammations, infections and blood purification, as well as cough, cold, bronchitis or other respiratory disorders, or urinary infection and kidney problems had similar floristic compositions. Mixtures used for nervous system disorders, anxiety and heart problems often had a similar composition.