Several theories have been proposed, the most consistent being that it acts in a similar fashion to NSAIDs by the inhibition of the cyclo-oxygenase pathways. However, paracetamol lacks both the peripheral anti-inflammatory and anti-platelet response seen with NSAIDs28 . More recently, it has been suggested that paracetamol may also be linked with both direct and indirect stimulation of the cannabinoid, nitric oxide synthase, and serotonergic pathways. Patients satisfying the inclusion criteria were selected during the study period from the operation register on a daily basis. After obtaining a written informed consent, sixty patients were recruited for this study. They were allocated into two groups of 30 each. 10 patients in group D and 08 patients in group P complained of nausea, none of the patients in either group had vomiting, bradycardia, and hypotension.