Patients will get Mucomyst 1000 mg by mouth twice a day for 30 days. Urine and serum will be collected at the beginning, , at 15 and 30 days after starting Mucomyst and 30 days after stopping Mucomyst. Portions of the blood and urine will be frozen and mailed to a special lab to measure the chemicals that determine the level of oxidative stress. The particular chemicals that will be tested for are isoprostane in urine and isoprostane, aconitase, glutathione peroxidase and total serum antioxidant stress in the blood. The special tests will be done by Dr. Valyathan's lab . Locally we will test blood and urine for proteinuria and kidney Fx.