Question: Hello - I have been taking 100 mg of allopurinol for a year to manage attacks of the gout. I increased the does to 200 mg for a week to see if this would help. I have reduced kidney function with a GFR of 69 as a result of a silent kidney stone that caused a blockage I was not aware of . No symptoms. Other kidney is normal and healthy. After a week, I stopped taking the higher dose of Allopurinol for fear that the higher dose might damage my kidney function. I am back to the usual 100 mg. dose. I get all panicked about my kidney function - some might say obsessively so. I am a male - 64 years of age. I have had 2 recent gout attacks - one that was aided with a cortisone shot however the current attack has been ongoing for 6 plus weeks now. Dr. prescribed various meds with no success. Also had a cortisone shot which assisted in reducing the pain however my toe is still swollen although less so now. I apologize for the length of my question.I had my uric acid tested as well as various blood tests. Results came back and my uric acid is 300. Why I was concerned about my GFR is that is has been rising over the past year from around the 56 - 58 mark 82, then 88 and then 92. As indicated, the test results that just came back pegged it at 69. That is when I thought I might have damaged my kidneys ( the damaged kidney still has very limited function ) by taking the increased dose of Allopurinol ( 200 mg ) for a week before stopping and reverting back to 100 mg. My GP has been out of the country for 6 weeks so I am dealing with a locum.