Sickle-leaf hare's ear (Bupleurum falcatum) has a long history of use in traditional medicine, particularly within Chinese and other East Asian herbal systems. It is a key ingredient in formulations such as Xiao Chai Hu Tang (Minor Bupleurum Decoction), which is traditionally used for conditions described as "alternating chills and fever," among other symptoms. The concept of "chills" in traditional Chinese medicine (TCM) may not align exactly with the Western medical understanding but often refers to symptoms experienced during febrile illnesses or "external wind-cold" invasions.

The use of Sickle-leaf hare's ear for chills is, therefore, primarily rooted in centuries of empirical observation and the principles of TCM rather than modern scientific validation. While some pharmacological studies have explored Bupleurum's anti-inflammatory and immunomodulatory properties, there is no robust clinical evidence specifically supporting its effectiveness in treating chills as defined in contemporary medicine. The available scientific literature focuses more broadly on its potential effects in liver health, inflammation, and immune modulation.

In summary, the association between Sickle-leaf hare's ear and the treatment of chills is justified by traditional use, with limited scientific investigation into this specific claim and no high-quality clinical trials substantiating its efficacy for this indication.