Treatment Considerations for Refractory Chronic Cough

Patients with refractory chronic cough are unresponsive to guideline-driven cough treatment.

This condition affects 8% to 10% of adults, and symptoms may include feeling a lump in the throat, dyspnea, and dysphonia.

The pathophysiology includes cough reflex sensitivity, central sensitization, peripheral sensitization, and paradoxical vocal fold movement.

Treatments include speech pathology interventions or medication, which is usually centrally acting neuromodulators.

Refractory chronic cough is more likely among smokers, those exposed to airborne pollutants, women, and those aged in their 50s through 70s.

A team of researchers addressed emerging treatments for chronic refractory cough in the December 2015 issue of British Medical Journal. They selected the American College of Chest Physicians’ guidelines on unexplained chronic cough as their reference treatment guideline.

Pharmaceutical treatment tackles cough more aggressively than speech pathology interventions, but at the expense of adverse effects.

Certain conditions such as asthma, gastroesophageal reflux disease, obstructive sleep apnea, angiotensin-converting enzyme inhibitor use, eosinophilic bronchitis, and rhinosinusitis may cause chronic refractory cough.

Many patients with chronic refractory cough will see improvement with corticosteroids for underlying bronchospasm or proton pump inhibitors for gastric reflux.

Because more serious disease can manifest as chronic refractory cough, clinicians should assess for airway cancers, structural lung disease, left-sided heart failure, and pulmonary embolism, if appropriate.

Coughing activates the cerebral cortex, so centrally acting agents such as gabapentin, pregabalin, morphine, and amitriptyline may help. Gabapentin in particular may be poorly tolerated, especially at higher doses, but tolerance for its related adverse effects improves over time.

Research indicates that morphine is usually well-tolerated, but it causes constipation (40%) and drowsiness (25%) in some patients.

Baclofen is suspected to be effective, but no randomized, controlled trials exist to support this claim.

A small trial found amitriptyline to be favorable over codeine and guaifenesin.

The researchers urged clinicians to consider speech pathology interventions and pharmaceutical treatment separately or together for refractory chronic cough.