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Honey is better than dextromorphan for treating children's coughs, reported seven newspapers (4 December 2007). The newspaper articles described a small trial in which buckwheat honey was found to give effective relief to night time cough symptoms. However, the trial only demonstrated honey to be superior to no treatment and not to dextromorphan.

On 4 December 2007 seven newspapers (1-7) reported that honey is better for treating children's coughs than dextromethorphan, the active ingredient in many over the counter cough medicines.
The reports are based on the results of a randomised controlled trial (8) conducted in the USA in which 105 children with coughs were given a single dose of buckwheat honey, honey-flavoured syrup containing dextromethorphan, or no treatment before bed. Night time coughing and sleep difficulties were rated by their parents and compared with the previous night. Improvements were seen in all three groups, the greatest in children given honey, where improvement was significantly greater that children given no treatment. The researchers concluded that honey was better than dextromethorphan or no treatment for relieving night time symptoms of coughs in children. However, there was no significant difference between honey and dextromethorphan for any outcome.
The newspapers provided accurate descriptions of the trial, repeating the researchers' conclusion. The research finding supports the use of honey for treating coughs, but not that it is superior to dextromethorphan. Although generally well conducted, the small size of the trial may account for the lack of statistical significance between honey and dextromethorphan and suggests that larger, longer term studies are needed to confirm the findings.

Evaluation of the evidence base for honey to treat cough due to upper respiratory tract infection (URTI) in children

Where does the evidence come from?

The study was carried out by researchers from the College of Medicine, Pennsylvania State University, led by Dr Paul, and was funded by the National Honey Board, an industry-funded agency of the US Department of Agriculture.

What were the authors' objectives?

To evaluate the effectiveness of a single dose of honey or honey flavoured dextromethorphan for treating nocturnal cough and sleep difficulties associated with URTIs in children.

What was the nature of the evidence?

This was a randomised controlled trial (RCT) involving 130 children aged between 2 and 18 years (105 of whom completed the study) with cough due to URTI. For inclusion in the trial, the maximum duration of the rhinorrhea and cough had to have been seven days, and the nocturnal cough frequency and effects on child and parental sleep for the previous night had to meet a minimum severity level, as assessed by parents using a validated questionnaire. Children were not eligible for the trial if they showed signs and symptoms of treatable diseases such as asthma, pneumonia or sinusitis, had a history of reactive or chronic respiratory disease, or took medications known to treat URTI on the previous night.

Children were stratified by age prior to randomisation (2-5, 6-11 and 12-18 years). The primary outcome was frequency of cough; secondary outcomes included cough severity, how bothersome the cough was and impact on sleep patterns. Symptom changes were assessed using a seven point Likert Scale, by parents via telephone interview the next day. A one point change in symptom score was considered to be clinically meaningful. Study coordinators, outcome assessors, and the children in the honey and dextromethorphan groups, were all blinded to treatment allocation.

What interventions were examined in the research?

Children were randomly assigned to receive buckwheat honey, an artificially honey-flavoured dextromethorphan preparation, or nothing in a 10ml syringe within 30 minutes of the child going to sleep. Dosage for the dextromethorphan preparation approximated that recommended in typical over the counter products for each stratified age group, and equivalent age-specific volumes of honey were given.

What were the findings?

In all three groups symptom scores for cough frequency and severity, the bothersome nature of the cough, and effects on child and parental sleep improved overnight. Honey gave the greatest improvement in symptoms for every outcome, and no treatment the least improvement.

For the main outcome of cough frequency, honey gave a 1.89-point improvement, dextromethorphan a 1.39-point improvement and no treatment a 0.92-point improvement, in symptom score. For secondary outcomes, all three treatments resulted in improvements of greater than one point on the Likert Scale. The overall rate of adverse events was significantly higher in the honey group, although there were no significant differences between groups when individual adverse events were analysed.

In a paired comparison with no treatment, honey was significantly better at improving cough frequency and the combined symptom score. There were no statistically significant differences for any outcome, when dextromethorphan was compared to honey or no treatment.

What were the authors' conclusions?

Parents rated honey more favourably than dextromethorphan or no treatment for the symptomatic relief of their child's nocturnal cough and sleep difficulty due to URTI.

How reliable are the conclusions?

This RCT was generally well-conducted, with appropriate methods of randomisaton and allocation concealment employed, to ensure groups were balanced at baseline, and participants and researchers were blinded to treatment allocation. A power calculation was performed, and the numbers of participants in honey and control groups marginally met those required to detect significant differences between the groups but the dextromethorphan group had slightly fewer participants than were needed. Overall, the trial appears to reflect a clinically relevant scenario, using appropriate treatment doses and investigating important outcomes using a validated tool. The conclusion that honey is deemed better by parents than no treatment or dextromethorphan for symptomatic relief of cough and sleep difficulty due to URTI is not supported by the results presented. From the results presented, it seems that the significant difference seen between all three groups for the primary outcome was driven by the difference between honey and no treatment. Pairwise comparisons showed no statistically significant differences in the rating by parents between honey and dextromethorphan. However the small sample size of the trial, particularly in the dextromethorphan group, may account for this lack of statistically significant difference. This therefore indicates that further studies would be needed to investigate the suggested superiority of honey over dextromethorphan.

Systematic reviews

Information staff at CRD searched for systematic reviews relevant to this topic. Systematic reviews are valuable sources of evidence as they locate, appraise and synthesize all available evidence on a particular topic.

There were no related systematic review identified on the Cochrane Database of Systematic Reviews (CDSR) and none on the Database of Abstracts of Reviews of Effects (DARE).