Some people are allergic to this plant, well known in Israel
I recently learned that it may help for a dimished the kidney function from getting worse [C.K.F] and even may improve the kidney function.

There are more plants which may be useful in these cases, like Cordyceps,Lezpedeza cap, Rheum palm ,Urtica diod root ertc
Nephrologists -as far as I know- in Isaell and in most of the Western world don't deal with plants . They are excellent in diagnosis but have no solutions to offer except for the end stage!
In  case you have a kidney problem of this kind [chronic kidney failure ] consult with a doctor who deals with herbs and food amd more  in conjunction with your nephrologist.
The other sad option is "follow up" [doing nothing] untill your are the list for transplantastion , G-d forbid.
May we all find a "shaliach tov" for seemingly untreatable conditions and ask daily in personal prayer for refua shlema.