Our aim is to investigate two major tendencies in nineteenth-century Brazilian alienism: mentalism and organicism, by conducting a descriptive study of original Brazilian documents on medical health treatments in the 1830s, 1840s and 1850s. Primary sources of Brazilian alienism were theses, memoirs, official reports, and documents written by clinicians and asylum directors. We analysed early mental treatment in Brazilian lunatic asylums, exploring the relative contributions of two main theoretical orientations: moral treatment (based on Pinel and Esquirol) and ‘medical-organicist therapeutic orientation’. Intertextuality was used to assess reports of medical organicist treatment in Brazil. We concluded that contemporaneous textual sources indicate that mid-nineteenth-century alienism in Brazil was predominantly influenced by organicism exported from European countries. Pinel’s mentalist view, nevertheless, remained the reference point for clinical issues associated with the doctor-patient relationship.