Eupatorium serotinum, commonly known as late boneset or late thoroughwort, is a perennial herbaceous plant native to North America. This fall-blooming species is widespread across the eastern United States, from Massachusetts to Texas, and inland to Minnesota and Nebraska. It typically thrives in open, moist environments such as prairies, meadows, and drainage ditches.
Growing one to two meters (40-80 inches) tall, late boneset features ovate leaves and produces clusters of small white flowers. These flowers, blooming in late summer or early fall, serve as a nectar source for insects, including monarch butterflies. Beyond its ecological role, the plant has also been noted for its historical use in traditional wellness practices.
Historical Applications of Late Boneset
The genus Eupatorium, which includes late boneset, holds a significant place in traditional medicine. Early pioneers and Indigenous North American communities used various species for their healing properties, often addressing fevers and general discomfort.
The common name “boneset” emerged from its traditional use in treating “break-bone fever,” a term describing the severe body aches associated with illnesses like dengue fever. Indigenous tribes, including the Iroquois, Cherokee, and Delaware, prepared boneset as a tea to support healthy body temperature, soothe inflammatory responses, and alleviate digestive issues. European settlers adopted these practices, recognizing boneset as a remedy for colds, fevers, and rheumatic pain throughout the 18th and 19th centuries. Its historical significance was further cemented by its inclusion in the U.S. Pharmacopoeia from 1820 to 1916.
Key Biological Properties and Compounds
Scientific investigations into Eupatorium serotinum and the Eupatorium genus reveal bioactive compounds that support their traditional uses. Phytochemical analyses suggest late boneset contains molecules contributing to antibiotic, anti-inflammatory, and antifungal actions. Specific compounds identified include caryophyllene oxide, which exhibits analgesic properties, and Pterocarpan, known for its antimicrobial, anti-inflammatory, and potential anti-cancer effects.
The Eupatorium genus contains secondary metabolites such as sesquiterpene lactones, flavonoids, and terpenes. Sesquiterpene lactones are associated with diverse biological activities, including anticancer, antiplasmodial, and antimicrobial properties. Flavonoids contribute to antioxidant and anti-inflammatory effects. These compounds interact, contributing to the plant’s health-related activities.
Mindful Considerations for Use
Despite its traditional uses, caution is warranted when considering late boneset. The U.S. Food and Drug Administration (FDA) classifies boneset, referring to species within the genus, as an “Herb of Undefined Safety.” A primary concern is the presence of pyrrolizidine alkaloids (PAs) in Eupatorium species, including Eupatorium serotinum. These compounds can lead to liver damage with prolonged ingestion, so internal use is generally advised against.
Pregnant and breastfeeding individuals should avoid late boneset due to documented adverse effects and potentially cytotoxic constituents. Side effects can include gastrointestinal upset, such as nausea, vomiting, and abdominal pain. Fresh plant material is more likely to induce these symptoms than dried forms. Some individuals may also experience headaches or skin irritation.
Late boneset may interact with certain medications, particularly those processed by the liver or affecting the immune system. This includes immunosuppressants, which late boneset might make less effective, and blood thinners, which could increase the risk of bleeding. Individuals with allergies to plants in the Asteraceae family, such as ragweed, may experience allergic reactions. Consulting a healthcare professional before using late boneset or any herbal remedy is strongly advised, especially for those with existing health conditions or other medications.