Delphinine is a toxic diterpenoid alkaloid found in plants from the Delphinium (larkspur) and Atragene (a clematis) genera, both in the family Ranunculaceae.

[1] Delphinine is the principal alkaloid found in Delphinium staphisagria seeds – at one time, under the name stavesacre, a very well known herbal treatment for body lice.

[7] A less antique and more accessible report is that of the USDA chemist L. N. Markwood, who also briefly reviewed the earlier isolation work.

[8] Notably, these early isolations were carried out without the aid of chromatography, since delphinine crystallizes readily from a petroleum ether extract after the typical acid-base cycling used in traditional plant alkaloid-extraction methods.

As a result of its early discovery and isolation in crystalline form (then considered a criterion of purity), the pharmacological properties of delphinine were extensively investigated in the 19th century, despite the fact that its molecular structure was unknown.