Psychoactive plants of the central Andean region (Bolivia, Peru and Ecuador excluding the eastern lowlands) are surveyed, emphasizing plants traditionally applied by healers (curanderos, shamans) and their clients/ patients for hallucinogenic and/or narcotic effects. Prevalent among these plants are the San Pedro cactus (Echinopsis pachanoi) used for a hallucinating decoction taken during ceremonies in northwestern Peru and southernmost Ecuador, but probably not, as often as claimed in Bolivia. Two other cacti may occasionally replace San Pedro (Armatocereus laetus, Melocactus bellavistensis), and a variation of other plants can be added to the San Pedro potion, but it is unclear if they have narcotic effects. The more potent and dangerous tree datura (Brugmansia spp.) were historically used in the region and are still taken in certain areas, e.g. as a supplement to San Pedro when shamans confronts complicated cases. However, Brugmansia tends to be used in secrecy since these plants are much associated with black magic and death, and locals believe that they mainly serve (the evil) to bewitch enemies. Tobacco (Nicotiana spp.) is always a component of psychoactive rituals, and has been administrated in dosages resulting in mind-altering effects and even hallucinations. Coca (Erythroxylum coca and E. novogratanense) are also important ritual plants, but have mainly stimulating rather than narcotic effects. Finally some psychoactive plants used in pre-Colombian and early postColumbian times have been abandoned, and the Vilca tree (Anadenanthera colubrina) was apparently the most important of these plants. Its seeds provided a hallucinating snuff inhaled via the nostrils, and paraphernalia that served to administrate this snuff are commonly discovered both in the highland along the coast. Other species claimed to have psychoactive effects are Coriaria ruscifolia and Pernettya prostrata.