Due to its long history of human propagation and the lack of discovered, definitively wild populations (Kowalczuk et al, 2014), researchers have not conclusively determined where seer’s sage (Salvia divinorum) originated. A 2010 phylogenetic study showed that of fifty-two other New World salvias (subgenus Calosphace), its closest known relative, Salvia venulosa, is native to Columbia (Jenks et al, 2010). However, S. divinorum is only endemic to the mountains of the Mazatec region of the state of Oaxaca, Mexico. Today this area comprises approximately 2,400 square kilometers in Southern Mexico; part of its eastern range was submerged following the creation of the Miguel Alemán Dam in 1954 (Cosby, 2011). Within its range, seer’s sage is found growing in cloud forests between 500 and 1,500 meters above sea level, where it favors moist, fertile soils near water sources (Casselman et al, 2014). S. divinorum was first propagated outside of Mexico in 1962 by the psychiatrist and ecologist Sterling Bunnell. Following the identification of S. divinorum as a new species in 1963, Bunnell donated clones to the University of California, Los Angeles (Siebert, 2003). These clones have since been spread and cultivated worldwide, and have been shown to survive and reproduce in other tropical locations with similarly suitable microclimates, such as Hawaii (Hanna, 1999).
Salvia divinorum blooms in response to short days with uninterrupted periods of darkness at least twelve hours in length. In its native range, it sporadically blooms between the months of August and March, although native populations of S. divinorum have yet to be observed producing mature seeds (Casselman et al, 2014; Valdes et al, 1987). The flowers, which have white corollas and purple calices, are not uncommon to cultivators outside the mint’s native range, and through hand pollination or natural methods growers can produce mature nutlets (Kowalczuk et al, 2014; Hanna, 1999).
Even when seed production is one of the aims of cultivation, however, S. divinorum produces few seeds, and those produced generally have low germination rates. Additionally, few of the seedlings that manage to germinate survive. Studies compiled by Jon Hanna on the seed production of S. divinorum demonstrated a seed set between 2.5 and 14.3 percent, with germination rates that varied from 17 to 33 percent. It has been suggested that most, or all, of the clones cultivated outside of Mexico are genetically identical, which may explain the low seed production and seed germination S. divinorum exhibits (Hanna, 1999). However, Casselman et al. (2014) note that the native organic methods of pollination of S. divinorum are unknown. Interestingly, some of the plant’s physical characteristics (flower dimensions and nectar qualities in particular) contribute to the suggestion that its natural pollination may be performed by an as of yet unidentified bird species. This hypothesis is also supported by the fact that hummingbirds have been witnessed to feed opportunistically on cultivated S. divinorum plants. In its native range, S. divinorum appears to exclusively propagate itself asexually through vegetative reproduction by rooting from branches that reach, or break and fall onto, moist soil (Casselman et al, 2014).
Seer’s sage, also known as ska maria pastora or simply salvia (Salvia divinorum), has been and is traditionally used by the Mazatec people of Mexico as both medicine and spiritual aid. The maladies they treat with S. divinorum include diarrhea, headaches, rheumatism, and panzón de arrego (“swollen belly”), an affliction the Mazatec claim is caused by a malevolent sorcerer (Casselman et al, 2014). Experiments with guinea-pigs conducted by Vincent Capasso and other researchers at the University of Napes Frederico II (2006) support its use for gastrointestinal ailments. An extract of S. divinorum leaves inhibited contractions in the guinea-pig ileum. They concluded the extract was successful because it reduced the transmission of the neurotransmitter acetylcholine by activating kappa-opioid receptors (Capasso et al, 2006). Butelman and Kreek (2015) note that the chemical constituent responsible for this effect, a diterpene called salvinorin A, is unique for a number of reasons. Salvinorin A is the only known plant-derived ligand that selectively targets kappa-opioid receptors (as opposed to mu-opioid receptors activated by morphine and other opioids). Activation of the kappa-opioid system mediates the effect of the mu-opioid “pleasure center,” among other behavioral functions. It is also structurally unrelated to any known opioid-receptor agonist. Salvinorin A is distinct in its method of action from other hallucinogens, which are largely nitrogenous alkaloids that bind to serotonin receptors (Butelman & Kreek, 2015).
Additionally, as diterpenes found in S. divinorum have been demonstrated to act as selective kappa-opioid receptor agonists, the plant may possess antidepressant properties, a theory that is anecdotally supported. It could assist researchers in discovering novel antipsychotic medications (Chavkin et al, 2003). In a letter that served as testimony to the Maryland state legislature, researchers at Johns Hopkins University School of Medicine wrote that research with S. divinorum taking place across the United States could also potentially lead to breakthroughs in the therapeutic treatments of Alzheimer’s, schizophrenia, bipolar disorder, dementia, pain, and drug addiction (Griffiths & Johnson, 2009).
Salvia divinorum and its psychoactive constituents are legally restricted in a number of countries, which may be due to its increased use, claims by vendors that its effects are similar to those of illegal drugs (DEA), and sensationalist media stories (Shafer 2008). Countries which have passed measures making either S. divinorum or salvinorin A (the primary chemical responsible for S. divinorum’s psychoactive effects) illegal to possess or sell include Australia, Belgium, Canada, Croatia, Czech Republic, Denmark, Germany, Italy, Japan, Latvia, Lithuania, Poland, Portugal, Republic of Ireland, Romania, South Korea, Sweden, and Switzerland, while countries that have prohibited the sale, but not possession, of either include Chile, France, Russia, and Spain. In Estonia, Finland, Iceland, and Norway the possession of S. divinorum requires a doctor’s prescription (Siebert 2015).
In the United States, S. divinorum is illegal to possess in 27 states, and another five states when specifically “intended for human consumption”. Age-restrictive measures have been passed in California, Maine, and Maryland (Siebert 2015). Opponents to the prohibition of S. divinorum claim that the plant does not pose a significant risk to public health or safety, and that regulations fail to align with science. No deaths have been attributed to its use, and legislation would severely restrict research into compounds with significant medical potential (Shafer 2008, Siebert 2015, Griffiths & Johnson 2009). The United States Drug Enforcement Agency’s attributed “overdose effects” include a “lack of coordination, dizziness, and slurred speech” (DEA). Federal legislation to ban S. divinorum was proposed in 2002, but did not pass (Siebert 2015). Congress was, in part, dissuaded from approving the bill by the Center for Cognitive Liberty and Ethics, which sent experts to testify on the “history, effects, medical use, and low abuse potential” of S. divinorum (Biore et al, 2001).
