The purpose of this study is selection of the best drug among three available drugs: ephedrine, lidocaine and ketamine with a low dose to reduce injection pain and hypotension and bradycardia due to propofol injection. This randomized double-blinded placebo-controlled clinical trial study perform on 140 patients 20-40 years in ASA class I, who are candidate for elective surgery and anesthesia induction with propofol and the first experience of anesthesia. Patients randomly allocate to receive ephedrine 0.1mg/kg (Group E, n = 35) or lidocaine2% (group L, n=35) or ketamine0.1mg/kg (group K, n=35) or normal saline (group N, n=35) in volumes of 2cc, intravenously 30 second before propofol injection. During slow injection of propofol, pain and its severity is assessed with 4 points scale (0=no pain , 1=mild pain with frown, 2=moderate pain with frown and whine , 3=sever pain with withdrawal movement of hand and squeal ).Then 1.5- 2 cc fentanyl and 0.5 mg/kg atracurium is injected and after 3 min ventilation, trachea is intubated.systolic, diastolic and mean blood pressure and heart rate are measured and recorded before induction, just before intubation and after tracheal intubation.finally we analyze the collected data with using statistical software.