Piboserod is a selective 5-HT₄ receptor antagonist which was marketed and manufactured by GlaxoSmithKline (GSK) under the trade name Serlipet for the management of atrial fibrillation and irritable bowel syndrome. In 2007 the Norwegian company Bio-Medisinsk Innovasjon AS (BMI) completed a clinical phase II study to investigate the effect of piboserod in patients with chronic heart failure.