Fentanyl is probably the most commonly used opioid in ICUs. Fentanyl is associated with coughing in upto 30% of patients. Usually its benign but may become explosive causing discomfort and increased intracranial and intra-ocular pressures. The various mechanisms proposed to explain fentanyl induced cough are inhibition of central sympathetic outflow leading to vagal predominance, histamine release or deformation of the tracheobronchial wall stimulating the irritant receptors.
Treatment is aerosol inhalation of Salbutamol, beclomethasone or sodium chromoglycate if needed.