The Objectives of this study is to evaluate the effect of Endosome and Apotel on postoperative pain in patients with upper limb fracture undergoing general anesthesia. This is a phase III, single center, double-blind, randomized clinical trial in which patients with upper limb fractures referred to the Gorgan 5 Azar Medical Education Center will participate. They will be assigned into two intervention and control groups (sample size=50) through block randomization. Major eligibility criteria include: aged over 15 years, anesthesia risk factors 1 and 2, upper limb fracture. Primary exclusion criteria include patients with uncontrolled diabetes, patients with ischemic heart disease and stroke. After the end of the surgery and in the recovery phase, both groups will receive Patient Controlled Analgesia (PCA). For the control group, the pain pump will contain 2 grams of Apotel, which will be diluted with 100 cc normal saline 0.9 %. For the intervention group, the pain pump will contain 2 grams of Apotel and 8 milligrams of Ondansetron, which will be diluted with 100 cc normal saline 0.9 % and will be delivered at the rate of 4 cc / hr. The pain relief will be evaluated for 24 hours. The main outcome measure in this study will be pain and the main influencing variables will be the type of treatment group (intervention group, control group), gender, age, and smoking.