Hi Dan,
I went through the same chemo regime of Cisplatin-Gemzar , which was later substituted with Carboplatin after two cycles because of rise in my creatinine. Since I was already a kidney transplant recipient, I was at major risk and was constantly monitored and the docs were very observant and I was admitted as an inpatient to make sure all the cisplatin is flushed out without fail.
My creatinine was at 1.5 at the end of chemo, and was in the same level for the first one year. But, slowly it started reducing and my report from last week showed it at 1.0 which is very very rare for me, with my kidney complications and the medicines that I take.Its been 2.5 yrs since my chemo. I didn't take any supplements particular for kidney function improvement. I asked my doc to reduce the dosage of my transplant medications to boost immunity and also to reduce toxicity for the kidneys. I take Vitamin C & E and that's pretty much it. I do exercise regularly and drink a lot of water.Hope this helps and I am sure yours will also reduce after sometime,since you are normal otherwise. But, it is better to check it with a nephrologist rather than just visiting your onco & urologist.
S R
Kidney Transplant 1998
Upper Tract TCC, Dec 2004
Native kidney Right Nephroureterctomy Dec 2004
Non invasive bladder cancer,High Grade, Ta,TURB Jan 2012
Native kidney Left Nephroureterectomy Feb 2012