Eupatorium perfoliatum — the wetland herb whose name comes from its use against 'breakbone fever,' brewed hot for the deep aches of flu and malarial-type fevers when there was nothing else to reach for.
Boneset sat on the winter and 'fever season' medicine shelf of rural Black Southern households as the go-to for flu and the shaking fevers that swept through. In places where malaria, dengue-type fevers, and influenza came hard and a doctor was unreachable, knowing the wetland plant that broke a fever was survival knowledge of the highest order.
Boneset was the premier American fever herb — a hot infusion induces sweating (diaphoresis) to break a fever, and the bitter sesquiterpene compounds have immune-stimulating and anti-inflammatory action documented in later research. Its very name records its reputation against 'breakbone fever' (dengue-type) and the bone-deep aches of influenza. It was a frontline remedy in the fever-ridden, mosquito-heavy rural South where chills-and-fever illness was a constant threat.
Use the dried aerial parts (leaves and flowering tops). Steep into a HOT infusion and drink warm to promote sweating and break a fever — the hot, bitter tea is the traditional method. Honey helps the bitterness. The herb is taken during acute illness, not as a long-term daily tonic.
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