Randomised clinical trial: gabapentin vs baclofen in the treatment of suspected refractory gastro-oesophageal reflux-induced chronic cough.

Background: Neuromodulators are considered potential therapeutic options for refractory gastro-oesophageal reflux-induced chronic cough. Aim: To compare the efficacy of gabapentin and baclofen in patients with suspected refractory gastro-oesophageal reflux-induced chronic cough.

Methods: Two hundred and thirty-four patients with suspected refractory gastro-oesophageal reflux-induced chronic cough, who failed an 8-week course of omeprazole and domperidone, were recruited into the open-labelled study and randomly assigned to receive either gabapentin (maximum daily dose of 900 mg) or baclofen (maximum daily dose of 60 mg) for 8 weeks as add-on therapy to the previous treatment. The primary end point was the successful rate of cough resolution; and the secondary end-points included cough sensitivity to capsaicin and gastro-oesophageal reflux disease questionnaire score and reported side effects.

Results: One hundred and eleven patients in the gabapentin group and 106 in the baclofen group completed the study. The overall success rate for cough resolution was comparable (57.3% vs 53.0%, χ2  = 0.357, P = 0.550) between the two groups. In parallel, cough sensitivity to capsaicin and gastro-oesophageal reflux disease questionnaire score decreased after treatment with either gabapentin or baclofen. However, gabapentin was associated with less frequent somnolence (20.5% vs 35.0%, χ2  = 6.156, P = 0.013) and dizziness (11.1% vs 23.9%, χ2  = 6.654, P = 0.010) than baclofen.

Conclusions: Gabapentin and baclofen have similar therapeutic efficacy for suspected refractory gastro-oesophageal reflux-induced chronic cough. However, gabapentin may be preferable because of fewer side effects. Trial Register: http://www.chictr.org/; No.: ChiCTR-ONC-13003066.