Background: The most commonly preferred treatment method for sacrococcygeal pilonidal sinus disease is surgery. Peroperative and postoperative hemorrhages may develop frequently because of the increased vascularity of the region. The aim of this study was to evaluate the effects of adrenalin, a potent vasoconstrictor agent, on pilonidal sinus operations in comparison to a control group. Methods: A prospective, randomized, double-blind, clinical study was designed and 51 patients with symptomatic, uncomplicated pilonidal disease were included (44 males and 7 females; mean age 24.5, range 16–44 years). Adrenalin 0.1 mg with 10 ml 0.9% NaCl (1/100,000 dilution) was injected through the incision tracts to all layers and the base of the incision area in group 1 (n = 21). The same process was applied to group 2 (n = 21) with 10 ml physiological serum solution. Then, after removal of the sinus and its tracks, a suction-type drain was placed in the pouch in all cases and the incision was primarily closed. Peroperative and postoperative hemorrhage, and operation time were accepted as the evaluation criteria. Cases were followed for 6 months postoperatively. Results: The amount of peroperative hemorrhage was 6.5 ± 3.5 ml in group 1 and 17.5 ± 9.5 ml in group 2 (p < 0.001). The postoperative hemorrhage was 11 ± 7.5 ml in group 1 and 13.5 ± 6 ml in group 2 (p > 0.05). The operation time was 14 ± 5 min in group 1 and 22 ± 8.5 min in group 2 (p < 0.05). No reactionary hemorrhage, hematoma or recurrence was seen during the follow-up period. Conclusions: Adrenalin injection is quite effective to decrease peroperative bleeding and operation time, but it does not decrease postoperative bleeding and the need for a drain.