Addictive Potential: None
Emergency Room Visits Yearly: Unknown
Mandatory Minimum Sentence: None
Mechanism of Action: MonoAmine Oxidase Inhibitor (MAOI)
Banisteriopsis caapi, also known as Ayahuasca, Caapi or Yage, is a South American jungle vine of the family Malpighiaceae. It is used to prepare the entheogenic brew Ayahuasca.
Banisteriopsis caapi contains the beta-carboline harmala alkaloids and MAOIs harmine, harmaline, and tetrahydroharmine. The MAOIs in B. caapi allow the primary psychoactive compound, DMT (which is introduced from the other primary ingredient, in traditional Ayahausca it is Psychotria viridis), to be orally active. The stems contain 0.11-0.83% beta-carbolines, of which 40-96% is harmine.
Banisteriopsis caapi is currently legal to buy, sell, and possess in the United States.
When ingested orally, MAOIs inhibit the catabolism of dietary amines. Sufficient intestinal MAO-A inhibition can lead to hypertensive crisis, when foods containing tyramine are consumed (so-called “cheese syndrome”), or hyperserotonemia if foods containing tryptophan are consumed. The amount required to cause a reaction exhibits great individual variation and depends on the degree of inhibition, which in turn depends on dosage and selectivity.
The exact mechanism by which tyramine causes a hypertensive reaction is not well understood, but it is assumed that tyramine displaces norepinephrine from the storage vesicles. This may trigger a cascade in which excessive amounts of norepinephrine can lead to a hypertensive crisis. Another theory suggests that proliferation and accumulation of catecholamines causes hypertensive crises.