San Pedro cactus may refer to several species of cactus potentially containing mescaline, particularly:
Echinopsis pachanoi (Trichocereus pachanoi, Trichocereus macrogonus var. pachanoi)
But also, less commonly:
Echinopsis cuzcoensis (Trichocereus cuzcoensis) Echinopsis lageniformis (Trichocereus bridgesii; Bolivian torch cactus) Echinopsis macrogona (Trichocereus macrogonus, Trichocereus peruvianus, Echinopsis peruvianus; Peruvian Torch cactus)
See also Psychoactive cactus Lophophora williamsii (peyote) Pachycereus pringlei (cardón)