Herbs that Release the Exterior

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Which herb treats bi syndrome (painful obstruction syndrome), especially in the upper body?
Qiang Huo treats wind-cold-damp bi in the upper body (upper limbs and back).
Du Huo treats bi syndrome in the lower body.

Source: Bensky, D. (2004). Chinese Herbal Medicine: Materia Medica. Seattle, WA: Eastland Press. pp. 20 [Q905]