This will be a randomized double blinded clinical study conducted in patients undergoing oral and maxillofacial surgery under general anesthesia. Lidocaine group will receive intravenous bolus 1.5 mg/kg at induction followed by continuous infusion of 2 mg/kg/hr until the completion of surgery.Normal saline group will receive same amount of intravenous normal saline .The primary outcome will be postoperative pain using the NRS scale during first 24 hours and time to first analgesic request

Inclusion Criteria:

• Adult patients 18-60 years of age
• Patients of ASA (American Society of Anesthesiologists) Class I or Class II (I- healthy with no systemic disease, II- mild systemic disease with no functional limitation) who require oral and maxillofacial surgeries under general anesthesia

Exclusion Criteria:

• Refusal to give consent.
• Hypersensitivity or allergy to the study medication.
• ASA physical status III or more.
• Subjects with known severe hepatic or renal dysfunction or cardiac dysrhythmia or atrioventricular block.
• History of taking opioids or antiarrhythmic drugs within 1 week of surgery.
• History of drug or alcohol abuse
• History of psychiatric disorders.
• Patients requiring emergency surgery.
• Patients unable to comprehend pain assessment