Ipomoea tricolor is a species of morning glory native to the New World tropics, and widely cultivated and naturalised elsewhere. It is a herbaceous annual or perennial twining liana growing to 2-4 m tall. The leaves are spirally arranged, 3-7 cm long with a 1.5-6 cm long petiole. The flowers are trumpet-shaped, 4-9 cm diameter, most commonly blue with a white to golden yellow centre.
Some people consider this plant to be an invasive weed due to its fast rate of growth and its prodigious seed production.
Their traditional use was first discovered by Richard Schultes in 1941 described Mexican Native American use, in a short report documenting the use going back to Aztec times cited in TiHKAL by Alexander Shulgin. Further research was published in 1960, when Don Thomes MacDougall reported that the seeds of Ipomoea tricolor were used as sacraments by certain Zapotecs, sometimes in conjunction with the seeds of Rivea corymbosa, another species which has a similar chemical composition, with lysergol instead of ergometrine. This more widespread knowledge has led to a rise in recreational use by people other than Native Americans.
The hallucinogenic properties of the seeds are usually attributed to ergine (also known as d-lysergic acid amide, or LSA), although the validity of the attribution remains disputed. While ergine is listed as a Schedule III substance in the United States, parts of the plant itself are not controlled, and seeds and plants are still sold by many nurseries and garden suppliers.
The seeds also contain glycosides, and these compounds are the likely cause of nausea reported by those who have eaten the seeds, although most experienced users attribute the effect to the commercial treatment of the seeds, as the nausea is much less common when the seeds are home-grown without any pesticides. However, minor to medium-level cramps and a mild headache is common in inexperienced users, due to the glycosides the seeds contain.