© 2022 Elsevier Masson SASObjective: This study aimed to demonstrate the efficacy of sildenafil citrate in order to improve the distal necrosis of randomized flaps in diabetic rats, and to explore new methods to reduce distal necrosis encountered in flap surgery. Materials and methods: This is an experimental study in rats. The rats were first divided into three groups: Control(C), Diabetes(D), and Sildenafil(S). Streptozotocin 40 mg/kg was administered intraperitoneally to the rats in groups D and S that would develop diabetes. Two days after the procedure, blood glucose was measured from the tail vein of the rats, and the rats with a blood glucose level of 250 mg/dL and above were considered diabetic. 7 × 3 cm McFarlane flap was randomly planned on the back of the rats. In the flaps, ischemia was measured at the 30th minute with Na fluorescein, flap necrosis was measured on days 4 and 7, and specimens were collected from the critical zone and distal zone regions for histological examination. Results: The comparison of ischemia and necrosis regions, ischemia was found to be more significant in groups D and S compared to group C (P < 0.05). In the comparison of necroses on days 4 and 7, it was determined that necrosis occurred significantly (P < 0.05) less in group S compared to the other groups. It was determined that necrosis in group D was significantly (P < 0.05) higher on days 4 and 7 compared to the other groups. Conclusion: The distal circulation is affected worse in randomized flaps in diabetes. Sildenafil citrate significantly increased the flap viability (P < 0.05).