IRCT2014072318389N2 IRCT 2014-09-24 Qom University of Medical Sciences and Health Services Vice chancellor for research The effect of Allopurinol on prevention of contrast-induced nephropathy The effect of sodium chloride hydration with and without allopurinol on prevention of contrast-induced nephropathy in high risk patients undergoing coronary angiography 2014-08-23 anticipated 140 Complete https://irct.ir/trial/16694 interventional Randomization: Randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Parallel, Purpose: Prevention, Other design features: Block Randomization: Block randomization is commonly used in two treatment situations where sample sizes for two treatments are to be equal or approximately equal. The process involves recruiting participants in short blocks and ensuring that half of the participants within each block are allocated to treatment “B” and the other half to “C”. Conceptually there are an infinite number of possible block sizes. Suppose we consider blocks of size four. There are six different ways that four patients can be split evenly between two treatments: 1. AABB, 2. ABAB 3. ABBA, 4. BAAB, 5. BABA, 6. BBAA The next step is to select randomly among these six different blocks for each group of four participants that are recruited. 2 Acute renal failure. Intervention 1: Interventional group: All patients will be received allopurinol (100mg, TDS) 24 h before administration of contrast agent plus intravenous hydration (1mg /kg/h Normal saline for 12 h pre- and post-contrast). Intervention 2: Control group: All patients will be received intravenous hydration (1 mL/kg/ h) Normal saline for 12 h pre- and post-contrast.