Rhubarb contains chemicals that might help heal cold sores and reduce swelling. Rhubarb also contains fiber, which might help reduce cholesterol levels and affect stomach conditions.

People use rhubarb for diarrhea, stomach pain, indigestion, symptoms of menopause, menstrual cramps, obesity, swelling of the pancreas, and many other conditions, but there is no good scientific evidence to support most of these uses.*

Botanical Name: Rheum Palmatum (Cut)/Rheum officinale (Powder)
aka: Chinese Rhubarb, Da Huang, Garden Rhubarb, Himalayan Rhubarb, Indian Rhubarb, Medicinal Rhubarb, Radix et Rhizoma Rhei, Rewandchini, Rhapontic Rhubarb, Rhei, Rhei Radix, Rheum australe, Rheum emodi, Rheum officinale, Rheum palmatum, Rheum rhaponticum, Rheum tanguticum, Rhubarbe, Rhubarbe de Chine, Rhubarbe Indienne, Rhubarbe Médicinale, Rhubarbe Palmée, Rhubarbe Potagère, Rhubarbe Turque, Ruibarbo, Siberian Rhubarb, Tai Huang, Turkey Rhubarb
Origin: India
Notes: OU Kosher Certified. Steam stearilized. Non-irradiated. Non-GMO. Vegan. Bulk sold and labeled as for further manufacturing. Individuals must exercise their independent judgment in determining its appropriateness for a particular purpose or use. As with any manufacturing process, we suggest a small, lab-scale manufacturing for evaluation purposes prior to full commercial manufacturing.
Specifications are subject to change without notice.

References
WebMD

* FDA disclaimer