How to tell how damaged are my kidneys from overdose?

Kidney OD?: The best way to tell if you have kidney damage from an overdose is by elevating blood levels of BUN, creatinine and potassium and declining values blood levels of CO2. Other signs are decreased urine output and swelling of the ankles. If you have acute renal failure its best management occurs in a hospital where blood levels can be monitored and appropriate medical action can occur if, needed.