Background: Functional endoscopic sinus surgery (FESS) has been recommended as a treatment option for chronic sinusitis patients who have failed to respond to medical treatment. In order to maximize the visibility of the operative site during functional endoscopic sinus surgery (FESS), it is critical to reduce bleeding. The goal of this study was to examine the effectiveness of dexmedetomidine and magnesium sulphate as hypotensive agents in FESS in adult patients in order to achieve a bloodless surgical field.