Talk to Nephrologist on Kidney Function Test

Hi, A friend recently suffered from sudden kidney stone pain and had to visit emergency to fix that. His ultrasound test found 5 calculis of less than 5 mm and one of these was located in ureter. Kindney and all other organs in KUB report were declared normal. His urine/blood test showed creatnine raised level of 1.7 mg/dL. While other parameters including proteinuria, BUN was within normal range. Nephrologist prescribed him UROCIT K and advised to repeat test after a week and the creatnine level dropped to 1.1 mg/dL. He was tole to repeat the test again with a gap of further one week and creatnine level further dropped to 1 mg/dL. He has now been told to comlete UROCIT K course to and increase water intake to resolve kidney stones issue. Any opinion or advise please.