Summary of characteristics of included studies
Study | Design | Age range (years) | Intervention | Comparator | Outcome measure |
Ahmadi et al 13 | RCT double blind | 2–5 | Honey | Diphenhydramine | Day time and night time cough frequency and severity (we converted this to a 3 point Likert scale) |
Ayazi et al 14 | RCT no blinding | 1–12 | Honey 1; honey 2 | Diphenhydramine | Nocturnal cough and sleep difficulty score (validated 5 item, 7 point Likert scale24) |
Canciani et al 19 | RCT double blind | 3–6 | Grintuss syrup | Placebo | Day time and night time cough severity (modified from validated questionnaire32) |
Cohen et al 20 | RCT double blind | 1–5 | Eucalyptus honey; citrus honey; labiatae honey | Placebo (silan date extract) | Cough score (validated 5 item, 7 point Likert scale24), effect on sleep and combination |
Cohen et al 21 | RCT single blind | 2–5 | Grintuss syrup | Carbocysteine syrup | Cough score (validated 5 item, 7 point Likert scale24) |
Gupta et al 22 | RCT double blind | 18–65 | Honitus cough syrup | Marketed cough syrup, containing diphenhydramine | Day time and night time cough frequency score (6 point Likert scale), throat irritation |
Miceli Sopo et al 18 | RCT no blinding | 2–14 | Wildflower honey+milk | Dextromethorphan; levodropropizine | Cough score (validated 5 item, 7 point Likert scale24) |
Nanda et al 23 | RCT blinding unclear | >18 | Honey+supportive treatments | Supportive treatments only (regarded as placebo) | Subjective symptom score, throat pain recovery, fever recovery |
Paul et al 24 | RCT partially double blind | 2–18 | Buckwheat honey | Dextromethorphan; no treatment | Cough score (5 item, 7 point Likert scale) |
Pourahmad and Sobhanian25 | Single blinded trial | intervention group mean (SD) 24.4 (7.4) comparator group mean (SD) 27.4 (6.2) | Honey+paracetamol, naproxen and chlorpheniramine | Paracetamol, naproxen and chlorpheniramine | Duration of signs and symptoms: rhinitis, muscle pain, fever, throat congestion, cough and sneezing, assessed by investigators |
Raeessi et al 26 | RCT double blind | 21–65 | Honey; honey+coffee | Coffee | Cough frequency (questionnaire) |
Raeessi et al 15 | RCT double blind | 21–65 | Honey+coffee | Prednisolone; guaifenesin (regarded as placebo) | Cough frequency (questionnaire) |
Shadkam et al 16 | Four arm RCT no blinding | 24–60 months | Honey | Dextromethorphan; diphenhydramine; supportive treatments also suggested to the other groups, including saline nasal drops and paracetamol | Cough score (validated 5 item, 7 point Likert scale24) |
Waris et al 17 | RCT double blind | 1–12 | Honey | Salbutamol syrup; placebo (brown coloured sugar syrup) | Cough score (validated 5 item, 7 point Likert scale24) |
RCT, randomised controlled trial.