Medicinal plants (MP) have been used world-wide for the treatment or prevention of health conditions and due to their natural origin; they have been historically considered harmless. Semi-structured interviews were carried out with an intentional sample of twenty plant vendors in the city of Diadema to explore their knowledge and beliefs on the safety and efficacy of MP. Different levels of perceptions about the safety of MP were found, varying from "completely safe" to "completely harmful". The majority of the interviewees declared that "if herbs have an effect, they are also likely to have a side effect", depending on many factors such as dosage, concomitant use of other drugs, characteristics of the plant material and consumer related factors, specially those related to pregnant women, children and elderly people. Thirty-nine unexpected events related to 21 species of MP were reported. One case of serious gastrointestinal disease related to the consumption of a contaminated "slim mixture" was also described. Adverse events and other problems that result from MP are relatively uncommon, but they are almost certainly underreported and occur more often than acknowledged. This study strengthens the call for further research and educational efforts into this complex area.

OBJETIVO: Apesar da riqueza da biodiversidade brasileira, não foram desenvolvidos, até o momento, fitoterápicos voltados para tratamentos psiquiátricos a partir desta flora. O principal objetivo deste estudo é documentar as plantas utilizadas pelos índios Krahô em rituais de cura, sobretudo aquelas com potenciais ações psicoativas. Esta etnia indígena ocupa uma área no bioma cerrado, numa região central do Brasil. Além disso, estes resultados foram comparados àqueles obtidos durante um levantamento bibliográfico realizado a respeito das plantas psicoativas utilizadas por outras 25 etnias indígenas brasileiras. MÉTODO: Os dois anos de trabalho de campo foram conduzidos utilizando-se métodos da antropologia e botânica. RESULTADOS: Sete xamãs locais foram entrevistados e indicaram 98 receitas preparadas a partir de 45 plantas para 25 usos, que parecem estar envolvidos a propriedades psicoativas. São eles: "para evitar ficar louco", "estimulante", "calmante", "para diminuir tremores", "para dormir por mais tempo", "para abrir a cabeça" e "para induzir o sono". Este artigo descreve também um levantamento bibliográfico que registrou 58 plantas utilizadas por 25 etnias indígenas brasileiras que, de modo similar, podem ter alguma ação psicoativa. CONCLUSÃO: É muito rica a terapêutica para males psicológicos/psiquiátricos a partir de plantas utilizadas pelos índios Krahô. Este mesmo fato ocorre entre outras etnias indígenas brasileiras. Futuros estudos de fitoquímica e farmacologia a serem realizados com estas plantas poderão prover a psiquiatria com novos medicamentos.

OBJECTIVE: In spite of the richness of the Brazilian biodiversity, no phytomedicines have been developed from this flora with the purpose of being used in psychiatric treatments. The objective of the present study was to document the use of plants with possible psychoactive effects in rituals performed by the Krahô Indians, who live in the cerrado savannahs biome in the central region of Brazil. Also, the present data were compared with the data obtained during a review of the literature on the use of psychoactive plants by 25 Brazilian indigenous groups. METHOD: The study was carried out during two years of fieldwork during which anthropological and botanical methods were employed. RESULTS: Seven local shamans were interviewed and they indicated 98 formulas, consisting of 45 plant species that appear to have psychoactive properties and were used in 25 different treatments. Some of the psychoactive properties were "prevention of madness", "stimulant effect", "tranquilizing effect", "prevention of tremors", "longer sleeping period", "open mind" and "induction of sleep". This article also describes the review of literature, which recorded 58 plants that may have psychoactive effects used by 25 Brazilian Indian cultures. CONCLUSION: The treatment of psychological/psychiatric disorders based on the plants used by the Krahô Indians is very rich. It is also observed among other Brazilian indigenous groups. Future phytochemical and pharmacological studies on these plants may develop new medicines to treat psychiatric disorders.

Investigação prévia mostrou que ratos privados de sono (REM SD) mostram acentuação de resposta a agonistas dopaminérgicos. As evidências indicam que essa ação parece ser mediada por supersensibilização de receptores dopaminérgicos pós-sinápticos. Com base nisso, foi feita REM SD em ratos com modelo experimental da doença de Parkinson, nos quais foi feita lesão eletrolítica bilateral de ambas as vias nigro-estriatais. Sete dias após a cirurgia os animais eram submetidos a REM SD por 72 horas. Imediatamente após o final deste período era feita observação em campo aberto para a ambulação, "rearing", "grooming" e latência. Em comparação com ratos não-privados foi observado aumento significativo na ambulação e "rearing", resposta que reapareceu após um segundo período de REM SD, realizado 21 dias após a cirurgia. Estes dados, de melhora de dois parâmetros de modelo experimental da doença de Parkinson, sugerem que a privação de sono pode ser útil nesta doença.

Previous investigations have shown that REM sleep deprived (REM SD) rats display an enhanced response to dopamine agonists. This action seems to be mediated through a supersensitivity of dopamine post-synaptic receptors. Accordingly, REM SD was performed on rats with an experimental model of Parkinson's disease. The animals were bilaterally lesioned in the nigrostriatal pathway through a stereotaxically directed electrical current. Seven days after the surgery the animals were REM SD for 72 hours and immediatelly after the end of this period were observed in an open field for ambulation, rearing, grooming, and latency. In comparison with non-deprived rats there was a significant increase in ambulation and rearing, a response that appeared again after a second REM SD period on day 21th after the surgery. These data of improvement of two parameters of an experimental model of Parkinson's disease suggest that SD may be useful in this condition.