Acute respiratory tract infections (ARTIs), including the common cold, influenza, and pneumonia, are quite common in children. On average, kids experience between three and six of these infections every year. Most cases resolve without any serious harm, but tens of millions of these infections require hospitalization each year across the globe. In fact, ARTIs account for a quarter of deaths in children under age five, with pneumonia by far inflicting the most casualties.

So, while ARTIs are common, they shouldn't be trifled with. And one thing you probably shouldn't do with such an infection is try to treat it with homeopathy. A recent systematic review of randomized controlled trials examining treatment of child ARTIs with homeopathic remedies found no evidence that they are effective in any way. The review was published to the prestigious Cochrane Database of Systematic Reviews.

Homeopathy is a system of alternative medicine in which substances are heavily diluted in water, sometimes by factors of trillions or more. At each dilution, the solutions are vigorously shaken in a process called "succussion," which supposedly releases the healing energy of the substances into the water molecules. Though the resulting "remedies" are essentially just water, because they have been diluted so heavily, homeopaths claim that they can treat all sorts of maladies. Strangely, they also claim that a more heavily diluted remedy is more potent, which defies established laws of medicine and physics. U.S. sales of homeopathic and herbal remedies totaled $6.4 billion in 2012.

Homeopathic remedies used for the common cold include arsenicum album (arsenic trioxide), euphrasia (eyebright plant), and natrum muriaticum (sodium chloride, aka table salt). There's also a flu remedy called oscillococcinum, derived from duck liver and heart.

If homeopathy's description wasn't evidence enough of its ineffectiveness, the new Cochrane review should do the trick. The reviewers, based out of the University of Queensland in Brisbane, Australia, scoured through the published literature searching for randomized, controlled trials "comparing oral homeopathy medicinal products with identical placebo or self‐selected conventional treatments to prevent or treat ARTIs in children aged 0 to 16 years."

Their search turned up eight suitable studies with a total of 1,562 subjects. Examining the research, the reviewers found broad methodological inconsistencies and a high risk of bias in many of the articles. In fact, three of the studies were directly funded by homeopathy manufacturers.

The highest quality studies with lowest risk of bias showed no evidence that homeopathy was effective at preventing or treating ARTIs compared to placebo. The most biased, lowest quality studies did find a few benefits, but the reviewers were dubious of their claims.

"One study showed a reduction in disease severity for the homeopathy group at some time points. The other study showed a reduction in number of respiratory infections over the following year in the treatment groups, although more than a quarter of participants were not accounted for in the results," the reviewers wrote.

After completing their thorough review of the evidence, the authors were unimpressed.

"There is no convincing evidence homeopathic medicinal products are effective in treating ARTIs in children."

Source: Kate Hawke, Mieke L van Driel, Benjamin J Buffington, Treasure M McGuire, David King. "Homeopathic medicinal products for preventing and treating acute respiratory tract infections in children." Cochrane Database of Systematic Reviews. 9 Sept 2018. DOI: 10.1002/14651858.CD005974.pub5