Brown colored urine is certainly not normal unless you consume large amounts of fava beans, rhubarb or aloe. here are some medications including ATBs, laxatives containing cascara or senna and a muscle relaxer. There are also disease conditions that can change your urine to a brown or tea color. These are based in the liver or kidney.
Have you been able to produce this unusual colored urine sample to your PCP for evaluation? If not you might want to have a sterile or clean covered container to do a urine catch. If you can do this be sure to refrigerate it and deliver it to your PCP office asap.
You may want post on MedHelp's Urology Forum. Please be assured that you are always more then welcome here. However this the Urology Forum may be able to offer you better suggestions....or at least more suggestions. Here's the link:
http://www.medhelp.org/forums/Urology/show/52
I encourage you to contact your physician and report the urine color. Please let us know how you are doing. I'll be thinking of you.
Peace,
~Tuck