About Thermopsis rhombifolia var. divaricarpa (A.Nelson) Isely
This flowering plant is a variety of Thermopsis rhombifolia, which is also commonly called prairie thermopsis. It belongs to the legume family and is native to North America, where it occurs across the Great Plains and extends into the lower canyons of the Rocky Mountains. Its natural habitat consists of dry grasslands and woodlands. It is a perennial herb that produces yellow flowers during the spring. T. rhombifolia contains multiple quinolizidine alkaloids: anagyrine, thermopsine, rhombifoline, cytisine, N-methylcytisine, 5,6-dehydrolupanine, and lupanine. Alkaloid content is highest in the plant's seeds. Documented poisoning cases from ingestion of this plant include the following events: After eating a handful of the plant's immature seeds, called "peas", a 6-year-old girl developed a headache 6–7 hours after ingestion. The headache lasted for 12 hours, and she also experienced mild vomiting. Another 6-year-old boy ate an unknown number of these peas, started vomiting about 4 hours after ingestion, had mild vomiting that persisted for 2 hours, and experienced nausea but no headache. In an additional case, an 8-year-old boy ate approximately 6 peas, began vomiting 3–4 hours after ingestion, and reported abdominal cramping and headache. Most of his vomiting happened in the first few hours, and his symptoms gradually went away over the following 24 hours. One 6-year-old boy ate 20 or more of the plant's flowers, and developed abdominal pain and cramps after about 45 minutes. He vomited 6–7 times over the next 8 hours. Within an hour of ingestion, he became drowsy and weak, and had multiple episodes of dizziness and stumbling that continued over the first few hours. After 4 hours, he developed a headache that lasted 10–12 hours. His blood pressure and heart rate were not significantly affected, and he was treated with activated charcoal. In a separate case, a 6-year-old girl ate 2–3 flowers, and developed nausea and lethargy within an hour. Her symptoms faded over the next 3–4 hours.
