Stimulation of the pharynx with a catheter introduced through the nose appears to be a valuable method for managing hiccups in conscious and anesthetized man. Immediate inhibition of hiccups occurred in 84 of 85 patients treated in this manner, of whom 65 were anesthetized. Hiccups recurred in some patients, but were successfully managed with the same maneuver. The area responding to stimulation is the middle of the pharynx, opposite the body of the second cervical vertebra, which is innervated by the pharyngeal plexus. The suggested mechanism of action is impulses arising in response to pharyngeal stimulation which may block or inhibit afferent impulses being transmitted through the vagi thus interrupting the hiccup reflex. No undesirable effects have been encountered as a result of pharyngeal stimulation.
Salem MR, Baraka A, Rattenborg CC, Holaday DA. Treatment of Hiccups by Pharyngeal Stimulation in Anesthetized and Conscious Subjects. JAMA. 1967;202(1):32–36. doi:10.1001/jama.1967.03130140090014