IRCT20130304012695N3 IRCT 2020-06-01 Tehran University of Medical Sciences Preemtive effect of intra venus Diphenhydramin injection before induction of anesthesiaon on attenuating airway and cardiovasculare reflexes during extubation of the endotracheal tube in Orthognathic Surgery. Preemtive effect of intra venus Diphenhydramin injection before induction of anesthesiaon on attenuating airway and cardiovasculare reflexes during extubation of the endotracheal tube in Orthognathic Surgery. 2019-07-06 anticipated 72 Complete https://irct.ir/trial/48503 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment, Randomization description: To randomize patients with inclusion criteria Block balanced randomization is used.Before studying, one of the person who is not a member of the research team performs the randomization process by using Random generator software, forms four blocks for the intervention and control group, Blinding description: The person who makes the medicine add a code to every single medicine . The person who injects the drug does not know the code. The patient is not aware of the type of injectable medication. The researcher is not aware of the type of drug during the study. 2-3 Condition 1: Pain after maxillofacial surgery. Condition 2: Pain and agitation after maxillofacial surgery. Intervention 1: Intervention group: 50 mg of diphenhydramine is injected intravenously before anesthesia and the degree of agitation, pain,coughing and hemodynamic changes during extubation, and the severity of pain in the recovery, nausea and vomiting and the amount of analgesic are evaluated during 24 hours after surgery. Intervention 2: Control group: They do not receive medication. No - There is not a plan to make this available Justification or reason for not sharing IPD is Undecided - It is not yet known if there will be a plan to make this available