Ethics approval and consent to participate
cough
This study was approved by the Food and Drug Administration (Investigational New Drug (IND) #142148) on March 1, 2021 and the University of Montana Institutional Review Board (#188 − 18) on March 25, 2021. All methods were carried out at the University of Montana in accordance with relevant guidelines and regulations. All participants signed an IRB-approved informed-consent form to participate in this research, which included an agreement to avoid new cough treatments during the study.