I think if I had to choose one, it would be parsley root in organic tincture form.
One can also buy it in a few produce departments..meijers sells it and if you can get fresh, make a tincture from some of it and one from the tops and after it is ready take 60 drops (2 dropperfuls 3-5 times a day. Also make a tea by boiling (preferably in distilled water which releases more of the valuable phytochemicals that help diseases for 15 minutes with a little of the tops and strain and drink. you can also juice it. You can also use dried bulk herb parsley root o make tinctures if fresh is not available.
it is important to note, though, that generally a single herb does not cure and detox but rather a comprehensive program. I outlined a very comprehensive program below in this forum 5 months ago that should help kidney patients no matter ho far gone they are told they are. Schulze said many got off dialysis and get a dead kidney working again in his book on the kidneys and he used the full incurables program with supporting herbs, foods etc specific for the kidney (or for whatever disease one was fighting to cure)
it is best to use organic tinctures when using herbs (organic or wild crafted contains 7-10 times more pytochemicals that prevent and cure diseases and the tinctures are more absorbable and last many years as well) The usual dose is 60 drops 3-5 times a day depending on how bad one is. Herbpharm is a brand I like or make your own tinctures using organic, bulk herbs and 80 proof vodka. Of course, herbdoc sells the best (schulze's) but he doesn't have a lot of single herbs but mostly formulas..his kidney tea, tonic and 5 day cleanse are quite good.
Some of the herbs I mentioned in my 30 steps and other posts for the kidney are (not an herb but very helpful) cordeceps and Agaricus bisporas extract (mushroom), parsley root (with parsley attached), burdock tincture, and more.
The greatest aids for this problem are juniper berries, marshmallow root, parsley, and Watermelon
seeds (see this post for more
for aid to the kidney and water retention see this post
also if retailing fluids take diaphoretic teas
some foods and additional herbs for the kidney
you might also try a kidney glandular to help rebuild your kidney.
If you get worst, take a look at the many posts I did on kidney disease (I know it is a lot)
Under eye circles are usually allergy related so an elimination diet for while to find out what you are allergic to might be helpful.