I'm A 44 YR. Old white female. I am in pain management. I get drug tested once a week. My Creatinine leves have been low, or so the Nurse Practitioner said. Over the last 2 years i have gained a 100 lbs due to being in a car wreck and cant get around as well. I do over eat. I am on Lasix and my "Levels" Hve been low for my tests. I have trouble urinating and i have pitting edima in my lower & upper legs. My primary Dr. prescribes me Lasix. When i go to my pain specialist i have to drink alot of coffee, water or cranberry juice plus take my water pill or i'm unable to urinate. Would this have an effect on my levels in my urine?