Chinese silk vine

Aching, stiff, cold joints that worsen in damp weather in a patient who also has pitting ankle edema and scanty urine

Lower back and knee weakness with joint pain in an older patient, where a short, supervised course inside a formula is acceptable

Overview. Chinese silk vine is a twining deciduous shrub of the dogbane family (formerly Asclepiadaceae), common on dry hillsides across northern China. The medicine, xiang jia pi, is the dried root bark, recognized by its strong, sweetish aromatic smell. It has a long use for rheumatic pain and edema, but it is a cardiac glycoside plant and belongs to the restricted group. Its trade names 'xiang wu jia pi' and 'bei wu jia pi' have led to substitution for the harmless wu jia pi (Acanthopanax gracilistylus root bark) with fatal results.

Clinical Notes. This is a herb to know so that you can recognize it, avoid it where it does not belong, and use it briefly where it does. The classical picture is cold, damp, aching joints with weakness of the back and knees plus fluid retention, in an older patient with sluggish circulation.

Chinese Medicine Profile. Temperature: warm, toxic. Taste: acrid, bitter. Channels: Liver, Kidney, Heart. Actions: Dispels wind-dampness and relieves painful obstruction in the joints; Strengthens the sinews and bones in weakness of the lower back and knees; Promotes urination and reduces edema, including the swelling of a failing heart in older texts; Mildly strengthens the heart (a cardiac glycoside effect that is also the source of its toxicity).