Gefapixant Citrate, a Selective P2X3 Receptor Antagonist, May Improve Cancer-Related Hypergeusia: A Case Report.

Patients with cancer frequently experience taste disorders that substantially affect their quality of life. Gefapixant citrate, a P2X purinoceptor 3 receptor antagonist, is an antitussive agent known to cause taste-related adverse effects. In this study, we report the clinical course of a patient with cancer who was administered gefapixant citrate for refractory cough, which improved preexisting hypergeusia. The patient was an 85-year-old woman with lung cancer and malignant pleurisy who experienced hypergeusia and hypergeusia-induced loss of appetite. After aggressive cancer treatments were discontinued, gefapixant citrate was administered to treat her refractory cough. The patient reported improvement in hypergeusia and oral intake, which was maintained for 3 weeks. Gefapixant citrate may improve hypergeusia and sustain oral intake in patients with refractory cough, suggesting its potential use in the management of hypergeusia. However, caution is required owing to its limited efficacy in treating cancer cachexia and possible taste-related adverse effects.