Two cases of nintedanib-induced diarrhoea treated using a 5-hydroxytryptamine type 3 receptor antagonist

Nintedanib has been used in the management of patients with idiopathic pulmonary fibrosis (IPF) and progressive pulmonary fibrosis (PPF) [1, 2]. The most common adverse event associated with nintedanib is diarrhoea. In the INPULSIS and INBUILD trials, >60% of patients reported diarrhoea [1, 2]. Antidiarrhoeal medications, including loperamide, are usually administered and are adequate in some patients. However, a significant proportion of patients continue to experience frequent diarrhoea, even after antidiarrhoeal treatment. In the INBUILD trial, ∼30% of patients who experienced diarrhoea at least once required dose reduction or discontinuation of nintedanib [2]. Hence, new treatments for diarrhoea are needed to improve quality of life in these patients. Ramosetron, a serotonin (5-hydroxytryptamine) type 3 (5-HT 3 ) receptor inhibitor used for diarrhoea-predominant irritable bowel syndrome (IBS-D), might be a suitable treatment for nintedanib-induced diarrhoea [3], and has a low risk of hard stool (1.11%) and constipation (1.11%) [4]. Nintedanib-induced diarrhoea may be controlled by ramosetron by modulation of intestinal motility as for irritable bowel syndrome #pulmonaryfibrosis https://bit.ly/3OQVAII