Abstract Background: Complete tumor elimination via transsphe-noidal surgical operation is frequently hard for large non-functioning pituitary adenomas (NFPAs). A confirmed medical treating might be beneficial for their managing. Aim of Study: To investigate the effectiveness of dopamine agonist medication in decreasing or avoiding the re-growing of NFPA after ward surgical operation. Patients and Methods: This was a prospective, randomized, clinical trial done in Al-Azhar University Hospitals was conducted on 20 patients experienced primary transsphenoidal surgical operation for pituitary adenoma management, the study was carried out through a period of 12 months from March 2020 to March 2021. Results: Tumour reduction rate of remaining cancer mass was significantly higher in medically-treated group, while tumour growing rate of remaining tumour mass was signifi-cantly elevated in controls. Conclusion: Cabergoline (dopamine agonist was an ef-fective medication for the treatment of remaining NFPA, and its usage was accompanying with an elevated tumour shrink-agerates.