A Cochrane review included 12 studies with a total of 578 subjects, mainly from high-income countries. The aim of the review was to assess the effectiveness and safety of interventions (excluding antibiotics and vaccines) to reduce the severity of paroxysmal cough in whooping cough in children and adults. Interventions included antihistamines, pertussis immunoglobulin, corticosteroids, salbutamol, tramadol and montelukast. Ten studies recruited children (N = 448), and 2 studies recruited adolescents and adults (N = 130). Only 6 studies (n=196) reported data in sufficient detail for analysis.
Included studies did not show a statistically significant benefit for any of the interventions (table ). Only one study comparing pertussis immunoglobulin versus placebo (n=47) reported data on adverse events: 4.3% in the treatment group (rash) versus 5.3% in the placebo group (loose stools, pain and swelling at injection site).
| Comparison | Outcome | Mean difference, MD (95% CI) | Participants (studies) |
|---|---|---|---|
| Diphenhydramine vs. placebo | Paroxysms of cough per day | 1.9 (-4.7 to 8.5) | 49 (1 study) |
| Pertussis immunoglobulin vs. placebo | Whoops per day (first week) | -3.1 (-6.2 to 0.02) | 47 (1 study) |
| Duration of hospital stay (days) | -0.7 days (-3.8 to 2.4) | 46 (1 study) | |
| Dexamethasone vs. placebo | Duration of hospital stay (days) | -3.5 days (-15.3 to 8.4) | 11 (1 study) |
| Salbutamol vs. placebo | Paroxysms of cough per day | -0.2 (-4.1 to 3.7) | 42 (2 studies) |
Comment: The quality of evidence is downgraded by study quality (inadequate or unclear allocation concealment and blinding) and by imprecise results (few patients and wide confidence intervals).