Treatments for subacute cough in primary care: systematic review and meta-analyses of randomised clinical trials

Background Subacute cough following a non-specific viral infection lasting 3-8 weeks is common. However, despite many treatment options there are no systematic reviews evaluating these. Aim To provide a systematic overview of treatment options and outcomes evaluated in randomised clinical trials (RCTs). Design And Setting Systematic review and meta-analyses assessing the overall effects of any treatment for subacute cough. Method The authors systematically searched PubMed/MEDLINE and the Cochrane Central Register of Controlled Trials (last search March 2017) for RCTs in adult patients with subacute cough. The authors considered trials evaluating any outcome of any drug or non-drug treatments, apart from traditional Chinese and Asian medicines. They combined treatment effects on cough-related outcomes in random effects meta-analyses. Results Six eligible RCTs including 724 patients were identified. These assessed montelukast, salbutamol plus ipratropium bromide, gelatine, fluticasone propionate, budesonide, and nociception opioid 1 receptor agonist and codeine. Five studies reported effects on various cough severity scores at various timepoints. No treatment option was associated with a clear benefit on cough recovery or other patient-relevant outcomes in any of the studies or in meta-analyses for cough outcomes at 14 days and 28 days. Reported adverse events were rather mild and reported for 14% of patients across all treatments. Conclusion Evidence on treatment options for subacute cough is weak. There is no treatment showing clear patient-relevant benefits in clinical trials.