OPIUM ALKALOIDS By N., Pam M.S. - April 7, 2013 alkaloids stemming from opium, of which there are over twenty. The main alkaloid is morphine- others consist of codeine, thebaine, and papaverine. OPIUM ALKALOIDS: "Papaverine is rarely used, but is an opium alkaloid." Related Psychology Terms OPIATES THEBAINE OPIUM MORPHINE BUPRENORPHINE PAPAVERINE PILOCARPINE OPIOIDS YOHIMBINE LEVORPHANOL Cite this page: N., Pam M.S., "OPIUM ALKALOIDS," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/opium-alkaloids/ (accessed July 23, 2019).