IRCT20101122005225N8 IRCT 2020-08-21 Tehran University of Medical Sciences Efficacy of low-dose naloxone for the prevention of acute remifentanil-induced hyperalgesia Evaluation of the efficacy of low-dose naloxone for the prevention of acute remifentanil-induced hyperalgesia in patients undergoing general anesthesia for hysterectomy 2017-08-23 anticipated 75 Complete https://irct.ir/trial/50283 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Randomization description: Patients are randomlely assigned into three equal groups using computer-generated random sequence and the sealed envelope method by an assistant not involved in the study, Blinding description: In this study, both the patients and the evaluators were blinded to the type of intervention. All drugs were labeled and similar in appearance. A trained nurse anesthetist collects the data in operating room and post anesthetic care unit and an anesthesia resident blinded to study groups collects the data in the ward. 3 Hyperalgesia. Intervention 1: first Intervention group (Remifentanil-Naloxone group ):patients receiving remifentanil 0.3 µg/kg/min and low dose naloxone 0.25 µg/kg/h in 50 ml normal saline. Intervention 2: Second Intervention group(Remifentanil ): patients receiving remifentanil 0.3 µg/kg/min). Intervention 3: Control group(control) : patients receiving an infusion of 50 ml normal saline. Yes - There is a plan to make this available What will be shared: IPD collected for the primary outcome measure only When: starting in November 2025 To whom: people working in academic institutions Conditions: only for academic and research goals Where to obtain: Via sending an Email for corresponding researcher How to obtain: proposal of the project and document of it's registration Comments: