Do Pain Medications Affect The Functioning Of Kidneys?

My mother is very ill with CHF and CKD. She is 83 years old and started with Sundowner type of dementia about 6 months ago. She started having flank pain, both sides this past weekend. Ironically her pain started at the hospital while she was there to get a blood transfusion because she has a gastric bleed that comes and goes over the past 6 months. She was given Oxycotin 10 mg which has helped the pain. Should we in all honesty be worried about the effect of the pain killer on the kidneys at this time or just be thankful for the pain relief?