This figure is a forest plot showing the relative effects on cough severity of antitussive opiates, the antitussive dextromethorphan, and protussive mucolytics. Effect sizes relative to placebo (with 95% CIs) are: for dextromethorphan, 0.54 (95% CI, 0.27 to 0.80; p=0.0008); for opiates, 0.63 (95% CI, 0.40 to 0.86; p<0.0001); for moguisteine, 0.62 (95% CI, 0.04 to 1.16, p=0.0366); and for mucolytics, 0.14 (95% CI -0.20 to 0.49; p=0.384). The studies showed heterogeneity (p=0.0023). The effects of dextromethorphan, moguisteine, and opiates compared with placebo on cough severity support a benefit of these therapies, but the evidence is insufficient to determine relative benefit among these therapies.

Figure 4Meta-analysis of data on cough severity

From: Results

Cover of Assessment and Management of Chronic Cough
Assessment and Management of Chronic Cough [Internet].
Comparative Effectiveness Reviews, No. 100.
McCrory DC, Coeytaux RR, Yancy WS Jr, et al.

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