A medicinal herb used to treat coughs. Xiao Shuwan secretly purchased it from a pharmacy, ground it into powder, and mixed it into Prince Ning's medicine. However, it was entirely unsuited to Prince Ning's condition of phlegm and blood stasis obstructing his lungs. Instead of helping, it trapped the phlegm deeper, worsening his illness and causing him to cough up dark crimson blood. Xiao Guiwan had previously known not to use it.
