Domperidone, a "hidden" neuroleptic, is used for symptomatic treatment of gastroesophageal reflux disease, despite its uncertain efficacy. The intravenous form was withdrawn from the market in the 1980s following deaths due to cardiac arrhythmias. QT prolongation leading to cardiac arrhythmias, including life-threatening torsades de pointes, has also been attributed to oral domperidone. In 2010, two case-control studies, one Canadian and one Dutch, showed that patients who died suddenly or had severe ventricular arrhythmias were statistically significantly more likely than controls to have been exposed to domperidone. In practice, given its uncertain efficacy and a disproportionate risk of sudden death and severe ventricular arrhythmia, domperidone should not be used.