Glossopharyngeal neuralgia (GPN) is a rare condition characterized by paroxysms of lancinating pain in the regions of the tonsil, ear, larynx and tongue. The pain is typically triggered by activities such as swallowing, speaking or coughing. Fifty-seven years old female patient had suffered paroxysms of severe pain in the unilateral region of the glossopharyngeal innervation for several years, and long term drug therapy result in serious pancytopenia probably due to carbamazepine. The patient with idiopathic glossopharyngeal neuralgia received glossopharyngeal nerve block and her symptoms were relieved completely. Glossopharyngeal nerve block with alcohol was done by extraoral approach and satisfactory results were obtained.