Can't Take Creatine...

What other supplements can I use to gain weight and mass naturally??

After visiting with my doctor, we agreed that taking creatine was too risky for me seeing that I only have one kidney. (Yes, I know that no studies have proven creatine being damaging to kidneys but I still don’t see it being worth the risk.) My doctor said that the creatine can affect on the gland in the kidney that controls the waste.

Anyway, I was wondering what people would suggest for good supplements to gain more muscle mass. I currently take fish oil, multivitamin, whey, and casein. I have taken Nitric Oxide in the past with very little results or gains.