Renal transplants Muslims often ask their doctors whether fasting Ramadan is safe. Scanty studies addressed this question with controversial results. This prospective study was undertaken to look for any clinical or biological changes during the month of the fast. Twenty two kidney transplant patients with stable kidney functions, who were transplanted for more than one year, and voluntary chose to fast during Ramadan in 1425 H (Oct - Nov2004), were studied. There were 10 men and 12 women, mean age 47±11.6 years (25-69 y). Mean age of graft 78.8± 61.7 months (14-250 m). The etiology of ESRD was unknown in 13 (59%) patients. Eighteen (82%) recipients had living unrelated donors. 19 patients were on triple immunosupressor regimen. Comorbide conditions were hypertension, dyslipidemia and diabetes mellitus found in 20, 9 and 5 patients respectively. Full clinical and biological assessment was done once during the month preceding Ramadan, once during Ramadan and once in the month following the fast. Medications were taken in two divided doses at sunset (time of breaking the fast) and pre dawn (before the fast). Unpaired 2 tail Student’s t test was used and p<0.05 was considered significant. All the included patients did fast the whole of the month of Ramadan, none of them experienced any undue fatigue, or any other symptoms compared to the period before the fast. Body weight, blood pressure, kidney function tests, blood sugar, lipid profile, and drugs blood levels were all stable without any significant difference during Ramadan compared to pre or post the fast. Fasting Ramadan in renal transplant recipients after one year of transplantation and with stable graft function is safe and well tolerated.