Just say no to homeopathic cough syrup! Actually, avoid all cough syrups.

On the pages of SBM we frequently discuss homeopathy, and rightfully so considering its position as one of the most pervasive yet dumbest forms of alternative medicine. Just yesterday our own Scott Gavura, who is neither pervasive nor dumb, wrote an excellent review of some recent improvements in the regulation of these ridiculous remedies in Canada, and I encourage readers to check that out. Sadly, despite numerous high profile setbacks for the practice, including a thorough trouncing by the Australian National Health and Medical Research Council in March, proponents of what is essentially the belief in sympathetic magic continue to clutter the pubmeds and interwebs with worthless studies.

You may think that you’ve heard it all when it comes to homeopathy by this point if you are a regular reader (homeopathic electricity???), and perhaps you have. Homeopathic research is certainly no stranger to exposing children to ineffective treatments, and proponents have often demonstrated extremely questionable ethical practices. So if you’ve kept up with the literature, this won’t surprise you one bit. Consider this post aimed more at those less familiar with just how bad it is out there, and how children are often victims of a world view that involves the religious-like belief in quackery.

The study in question, and questions about the study

The study in question, “Does additional antimicrobial treatment have a better effect on URTI cough resolution than homeopathic symptomatic therapy alone? A real-life preliminary observational study in a pediatric population“, was published in the August 2015 open-access online journal Multidisciplinary Respiratory Medicine. You too can publish a paper in this journal for the low, low price of just under $2,000 (for “article-processing“). After reading this paper, I’m not confident in their editorial process or claims of being peer reviewed.

The title is a monstrosity that pretty much stands on its own as evidence for why the ensuing paper is garbage. In fact, it might be the most ridiculous study I’ve encountered in pediatric medicine. Never mind. It would actually be funny, however, if not for the glaring ethical violation perpetrated on helpless children.

The lead researcher, who is featured here on Boiron Italy’s website, was likely inspired by his 2013 study showing that a homeopathic cough syrup (produced by Boiron) had minimal clinical impact in adult patients diagnosed with acute bronchitis when he decided to test the same remedy in children. Wait, that’s not exactly right. He actually decided to throw ethics, equipoise, and the standard of care out of the window and expose children diagnosed with uncomplicated viral upper respiratory tract infections (colds) to a full course of antibiotics as well as the same homeopathic remedy.

The reasoning for including antibiotics instead of a placebo control in this trial? According to the authors, cough is a common symptom in children with upper respiratory tract infections and, unfortunately, antibiotics are often prescribed for viral etiologies. They took it upon themselves to see, just in case decades of evidence and basic science were wrong, if antibiotics might actually be effective in treating cough in children with colds. Like the king of the Britons, I am continually amazed by this new learning.

Does it get worse?

It gets worse:

The aim of this preliminary study was to evaluate if the addition of antibiotics to a symptomatic treatment (homeopathic syrup) improves cough resolution in pediatric patients with acute cough due to uncomplicated URTI.

Referring to a homeopathic syrup as a symptomatic treatment begs one very concentrated question: that it actually reduces symptoms. And isn’t the whole point of homeopathy to treat the “whole person” rather than just a symptom? The totality of evidence, not to mention those pesky fundamental laws of physics and chemistry, cannot be ignored because of one questionable study in adults with bronchitis. Why is it included at all? Why did they choose to compare antibiotics plus homeopathy to homeopathy alone instead of antibiotics to a placebo if their goal was to investigate the role of antibiotics in reducing the severity and duration of cough? Why did they choose a “real-life” approach instead of one that actually might address their claimed endpoints?

The answer is pretty clear in my opinion, although I must admit that I don’t have an inside track to their innermost thoughts. It could be that they are just incompetent and don’t understand trial design. No, I doubt that. I think that it is considerably more likely that this trial was designed with the intention of using it to claim that the homeopathic remedy works and that the antibiotics were a not-so-clever distraction. The logic that they use to determine efficacy of the homeopathic remedy is also not very impressive. Have I mentioned yet that the authors, who claimed no conflict of interest, acknowledged Boiron for their “non-binding financial contribution?”

What did they actually do?

The study, which took place in Italy, was “conducted according to the Helsinki declaration” and approved by an institutional review board. More on this later. Eighty-five children between the ages of 4 and 15 years with cough caused by non-complicated colds were split into two groups. One received a homeopathic syrup produced by our friends at Boiron four times daily for ten days. The other received the same remedy for ten days plus a concurrent seven days of an oral antibiotic regimen.

For 28 days following initiation of their “treatment,” subjects/parents filled out a daily cough diary which assigned their symptoms a score from 0 (no cough) to 5 (constant distressing cough). Adverse events were also discussed and cataloged at the end of the 4 week study period. When all was said and done, they found that both groups did exactly the same in regards to symptom resolution. Cough generally started getting better after a few days and in most patients was completely resolved by the end of the study. A small percentage of patients in both groups continued to have mild cough.

In regards to safety, there were no significant adverse events in either group. As would be expected, however, there were more reports of mild side effects in the group receiving an antibiotic. These side effects consisted of the already well-established most common side effects associated with antibiotics, namely diarrhea, vomiting, and rash.

The predictable conclusion

So how did the authors come to the conclusion that homeopathy worked for cough in these children, even though that supposedly wasn’t what they were investigating? Remember, the whole point of their study was to see if antibiotics reduced cough severity and duration during uncomplicated colds wink-wink-nudge-nudge. Here you go:

Our data suggest an antitussive efficacy of this homeopathic syrup in children since the time-courses of the VCD severity score in the syrup treated children of this study resulted overlapping to that obtained in syrup treated adults in a randomized, double-blind placebo-controlled trail.

In case you didn’t catch that, they concluded that the homeopathic cough syrup worked in the current study’s pediatric population because the subjects did as well as the adults in the “treatment” arm of their prior study. The prior study, like the overwhelming majority of homeopathy research, was entirely consistent with the much more plausible conclusion that the minimal clinical effect was a mixture of placebo effects and statistical noise. All the subjects in both studies simply followed the expected course of cough symptoms caused by colds when no treatment is provided.

According to actual science, cough caused by uncomplicated colds follows a typical course. Prospective cohort studies have shown that it takes ten days for about half of kids to stop coughing, and about 10% of cough persists at 25 days. In the current study, most subjects improved noticeably within a few days with the majority experiencing steady improvement and complete resolution of their cough by two weeks. And roughly 15% had persistent, although milder, complaints of cough at the end of the 28 day study period. So neither the antibiotics or the syrup had any positive effect.

Somehow this study was approved by an IRB despite the complete lack of equipoise. There is absolutely no question that antibiotics do not help children get better more quickly when they have an isolated viral infection. And antibiotics are not risk free, which is even acknowledged in the paper. In addition to the risk of inducing resistance in potentially pathogenic bacteria living on and within a patient, antibiotics can result in a variety of complications ranging from the mild (upset tummy) to the deadly (severe allergic reaction or skin sloughing off from head to toe). I’m not convinced that the authors or the IRB are actually familiar with the ethical principles delineated in the Declaration of Helsinki.

My conclusion: Sometimes you are better off doing nothing

There are no effective treatments for the cough caused by an uncomplicated common cold in children or adults. Not cough suppressants, not antibiotics, and especially not homeopathy. Unfortunately, the problem of prescribing antibiotics for patients with viral infections has long been recognized in conventional pediatrics, and we are working on it with public and professional educational campaigns such as Choosing Wisely. I’ve actually written about the overuse of antibiotics in children in the past.

The study discussed in the post adds nothing to what we already know about the pathophysiology and clinical course of the common cold in children. It has uncovered nothing that isn’t already well documented regarding the treatment of the symptoms of the common cold. What it does do is once again demonstrate that homeopathy is ineffective nonsense unworthy of additional resources being spent on further study. And it illustrates how belief, and possibly financial motivation, can result in poorly designed research and incoherent conclusions.


Posted by Clay Jones

Clay Jones, M.D. is a pediatrician practicing at Newton-Wellesley Hospital in Newton, MA, and a regular contributor to the Science-Based Medicine blog. He primarily cares for healthy newborns and hospitalized children, and devotes his full time to educating pediatric residents and medical students. Dr. Jones first became aware of and interested in the incursion of pseudoscience into his chosen profession while completing his pediatric residency at Vanderbilt Children’s Hospital a decade ago. He has since focused his efforts on teaching the application of critical thinking and scientific skepticism to the practice of pediatric medicine. Dr. Jones has no conflicts of interest to disclose and no ties to the pharmaceutical industry. He can be found on Twitter as @skepticpedi and is the co-host of The Prism Podcast with fellow SBM contributor Grant Ritchey.