Direct laryngoscopy and passage of endotracheal tube through the larynx is a noxious stimulus, which can provoke untoward response in the cardiovascular, respiratory and other physiological systems. Gabapentin, is 1-aminomethyl cyclohexane acetic acid.Gabapentin is structurally related to the neurotransmitter gamma-aminobutyric acid (GABA). Gabapentin act in central nervous system CNS), it acts by decreasing the synthesis of neurotransmitter glutamate and by binding to the alpha 2 delta subunits of voltage dependent calcium channels.