Chronic refractory cough: What to do when inhalers, nasal sprays and pills do not work

Abstract

Chronic cough in patients with a normal chest radiograph is rarely due to a sinister condition, it may have a profound impact on quality of life and contribute to anxiety and depression. Approximately one third of patients with chronic cough will not improve with the anatomic diagnostic approach recommended by the American College of Chest Physicians (ACCP) cough guidelines. Various terms, including cough hypersensitivity syndrome, unexplained, idiopathic or chronic refractory cough (CRC), refer to cough that does not respond to the traditional anatomic diagnostic approach. The recently updated ACCP cough guidelines recommend speech pathology therapy (SPT) for patients with CRC. The SPT program entails patient education, cough trigger avoidance, cough suppression techniques and psychoeducational counseling. For those cases that do not respond to SPT, neuromodulatory agents including opiates, amitriptyline, baclofen, gabapentin and pregabalin may provide some benefit but side effects are often limiting. Research to identify effective neuromodulators has isolated several vagal afferent receptor antagonists that initially appeared promising but have either not been effective or have had intolerable side effects. Moreover, the effects of these medications on capsaicin sensitivity may not be predictive of their effects on chronic cough. Hopefully, future research will identify effective agents for CRC with satisfactory side effect profiles.