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BBC’s You and Yours programme (a lunchtime consumer programme) ran a good piece on “Helps Stop Snoring”, a dubious herbal “remedy” for snoring. They picked up the story from my site. Listen to the programme [mp3 file]

“Helps stop snoring” claims to work on the basis of a clinical trial. But the trial is flawed in many ways. In addition the author, Dr Andrew Prichard, seems to have quite forgotten to mention that a Helen Prichard who lives at the same address holds 2000 shares in the company that makes this wonder cure. [transferred from old improbable science page].

My pharmacological curiosity was stirred by a TV advertisement for a spray that, it was claimed, could stop you snoring. It’s hardly a life threatening condition, but it can be marriage-threatening. But what’s in it, and does it work?

A visit to the web site of Essential Health Products Limited looks promising. Their claim is this.

Many products claim to have undergone tests, but Helps Stop Snoring is the only natural snoring remedy in the UK have undergone to a full, double blind clinical trial, conducted by a practicing Ear,Nose and Throat Consultant Surgeon.
Lasting over 18 months, the trial involved 140 snorers and their partners, and the results showed a headline success rate of 82%. The trial was conducted by Andrew Pritchard FRCS, Ear Nose and Throat Consultant at the Royal Shrewsbury Hospital and one of the UK`s leading specialists in the field of snoring and sleep disorders.
In a further first for a snore remedy the results of the trial were published in Phytology Research, an international journal, in October 2004.”

This claim was not so easy to check because the manufacturer mis-spells both the name of the author and the name of the journal. The paper in question seems to be this. Prichard AJ., The use of essential oils to prevent snoring Phytother Res. 2004 18(9), 696-9 [get the pdf].

Sadly this paper is not very convincing. The paper does describe the work as “preliminary”, but the manufacturer’s web site does not. There’s a surprise.   For those who are interested, here are a few details.

140 adult snorers were recruited to the study via a snoring clinic. Snorers were randomly allocated to receive a metered dose of “Stop snoring “gargle, “Stop snoring ” spray or placebo gargle (there was no placebo spray at all). It isn’t obvious what placebo could mimic the peppermint, lemon, clove, thyme, eucalyptus and pine oils that the “remedy” contains (among other things). Their concentrations aren’t stated. The paper makes no mention of what was used as placebo, but Dr Prichard tells me “The content of the placebo could not be an essential oil. I have been told by the manufacturer that we used a sugar type mix”. Actually it contained water, sodium saccharin, polysorbate 20, potassium sorbate and citric acid. It would be have been obvious tor the patient whether they got the placebo or not.

“A simple comparison was made between the 14-day control period and the 14-day period of ‘treatment’ either with product or placebo. Statistical analysis was performed using the Wilcoxon non-parametric test.”

Figure 4. Placebo gargle

Figure 2. “Stop snoring” spray

The comparison that is made is before and after in each treatment group, rather than comparing the groups. The eminent statistician, Stephen Senn, has some trenchant criticisms of this sort of experimental design.

Senn points out that “Having made the mistake of using the within treatment group to baseline comparison he ought to then use the Wilcoxon signed ranks test rather than the rank sum but he doesn’t say which”. The results are pretty odd too. In the placebo group, 4 out of 11 patients show a big reduction in snoring severity (Fig. 4). In the spray group, a smaller proportion, 5 out of 28 show a big improvement (Fig 2). The changes in the rest of the patients are mostly very small, but there are more slight improvements in the spray group than in the placebo group. The percent of patients that “improve” (by any amount, however small, is therefore bigger in the spray group than control, but the difference in mean snoring severity was much smaller

Financial interests in the snoring study

Sadly, it is essential to consider vested interests in drug assessment, as I have noted below (and here, and here). Prichard’s paper states openly that it was “Sponsored by Essential Health Products Ltd, 4 Top Farm Barns, Pitchford, Shropshire, SY5 7DW, UK.”  That doesn’t mean it’s wrong, though the bias associated with sponsorship is well known,

But there is no mention of shareholdings

Companies House will, only £1, sell you company reports. The records show that Helen Jane Prichard, holds 2000 shares in Essential Health Products Ltd.

Is this just a coincidence of names? I think not. If you look up. Dr Andrew Prichard in the phone book, you see that his address is exactly the same as that of Helen Jane Prichard.

Oh dear: looks like yet another undisclosed financial interest in a clinical study.

Many thanks to the inimitable Ben Goldacre fot the totally over-the-top link to this item: it has done wonders for my hit rate.

Boots the Chemists is selling the same stuff

True to their philosophy of making money and never mind the evidence, the “Boots Alternatives” range of snake oil products has, for £14.99, exactly the same stuff. They claim the Boots
Alternatives Snoring Remedy
is “effective in reducing snoring for 4 out of 5 users”. The “4 out of 5” was what Essential Health Products told Boots, so it must be based on Figure 2, above.

Enquiries to Boots about this product have not been answered or have been answered inaccurately. See also below for Boots miseducation pages.
And here’s the ironical bit. Boots web site makes a big point about CSR (Corporate Social Responsibility).  (Thanks to Sean
for spotting this.)


As you may have noticed, that’s the tagline which in 2005 we adopted as the sign-off to all our advertising. But it’s much more than just a slogan. It’s a concise statement of our entire corporate strategy. Our aim is to make Boots the world’s best health and beauty retailer, and we’re 100% clear that the unique trust in which we are held provides the key to achieving this. Which means, of course, that those two words are also the rationale for all our CSR activities. Everything we do that builds trust is good for our business; anything which could compromise it, a risk we can’t afford to take.”

Trust Boots to provide straight answers.

They must be joking.

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