Compound Monograph
Protopine
Protopine is an isoquinoline alkaloid found in poppy-family plants such as California poppy and corydalis.
Classification
Protopine is an isoquinoline alkaloid, part of the alkaloids class. Nitrogen-containing, often bitter and physiologically potent compounds — the group behind many of the strongest plant medicines and poisons.
Where Does It Come From? (5)
Protopine is a naturally occurring isoquinoline alkaloid, found in California poppy, Corydalis, Bleeding heart and 2 other sources. It is flagged as moderately toxic.
Research & Evidence
Protopine is an isoquinoline alkaloid occurring in many members of the poppy and fumitory families, including California poppy and corydalis, herbs traditionally used for their calming and sleep-supporting properties. In laboratory studies protopine has shown a range of activities, including effects on smooth muscle, platelet aggregation and various neurotransmitter and enzyme systems, which may contribute to the traditional uses of the plants that contain it. Robust human clinical data are limited.
Toxicity & Safety
As a minor constituent of herbs that have a long history of traditional use, protopine is generally encountered in small amounts and considered moderate in toxicity. Concentrated alkaloid exposure has not been well characterised for safety, so the usual caution around alkaloid-containing botanicals applies.