The increasing number of opioid users among chronic pain patients, and opioid abusers among the general population, makes perioperative pain management challenging for health care professionals. Anesthesiologists, surgeons, and nurses should be familiar with some pharmacological phenomena which are typical of opioid users and abusers, such as tolerance, physical dependence, hyperalgesia, and addiction. Further clonidine also reduces intraoperative requirement of opioid analgesics as compared to normal saline group. Total amount of rescue analgesia needed in 24 hour was also significantly less in clonidine group as compared to placebo group. Intraoperatively more fentanyl required in placebo group as compared to clonidine group (p<0.05).