Wednesday, 20 March 2013

Vicks, feet, and a whole load of nonsense.

And so it was that I ventured onto Facebook last night, for the first time in a while. And what I discovered there was an intriguing post about putting Vicks Vaporub on your feet to cure a cough.

A very quick google search suggests this is a long-standing bit of nonsense that's been doing the rounds with pretty much exactly the same wording for years. I thought it might be worth revisiting. so, here it is in its entirety, with my skeptical, critical thinking thoughts inserted in blue. I guess its a bit of an example about how to think about claims that appear at first glance to be too good to be true:

"Some of us have used Vicks Vaporub for years for everything from chapped lips to sore toes and many body parts in between. <Wait, What? Who uses Vicks Vaporub for chapped lips? I've never heard of anyone do this, ever. Firstly, it would sting lots, and secondly it could potentially be highly toxic, given its essential oil content, and aspiration risk when swallowed due to petroleum. I wouldn't put the stuff anywhere near my mouth.> But I’ve never heard of this. And don’t laugh, it works 100% of the time <100% of the time? Nothing in medicine works 100% of the time, so alarm bells are ringing loudly, unless this is the single most important medical discovery that's ever happenee, ever.>, although the scientists who discovered it aren’t sure why. <what scientists?>

To stop night time coughing in a child (or adult as we found out personally), put Vicks Vaporub generously on the bottom of the feet at bedtime, then cover with socks. <Feet seem to be a favourite of the quackery world, what with detox patches, reflexology and all that sort of thing. Alarm bells are a lot louder already. Why would Vicks be particularly effective on your feet? Is this as compared to any other parts of your body, or compared to nothing at all? Wouldn't it sting, and could it have potential to cause sensitisation in the area? Where is the prior plausibility here?>  Even persistent, heavy, deep coughing will stop in about 5 minutes and stay stopped for many, many hours of relief. <A coughing fit usually does stop after a few minutes of its own accord regardless of treatment. If it doesn't, and you're coughing constantly for more than 5 minutes, you probably need to be checked out by a doctor.> Works 100% of the time and is more effective in children than even very strong prescription cough medicines. <There are very few prescription cough medicines, on account of the fact that most preparations for cough don't really work anyway.Again, this 100% of the time claim is quite extraordinary and would require major clinical evidence to back it up.> In addition it is extremely soothing and comforting and they will sleep soundly. <Is the stinging, cold sensation you get with menthol really soothing?>

Just happened to tune in A.M. Radio and picked up this guy talking about why cough medicines in kids often do more harm than good, due to the chemical makeup of these strong drugs so, I listened. <What guy? What radio station? What are you on about? The only medicines now available for coughs in children OTC in the UK are glycerol and simple linctus paed- basically, sugary water. No "strong drugs here".> It was a surprise finding and found to be more effective than prescribed medicines for children at bedtime, in addition to have a soothing and calming effect on sick children who then went on to sleep soundly. <Where is this finding published? What sort of a study was it and how was it designed? How many participants were there? Was there a control group, or a comparator group and if so, what was the comparator? As it happens, none of these questions really matter given the studies themselves don't actually exist>

My wife tried it on herself when she had a very deep constant and persistent cough a few weeks ago and it worked 100%! <anecdote. It worked 100%, but in one person? This doesn't even make sense.> She said that it felt like a warm blanket had enveloped her, coughing stopped in a few minutes and believe me, this was a deep, (incredibly annoying!) every few seconds uncontrollable cough, and she slept cough-free for hours every night that she used it. <I'd imagine it would actually just feel like you had some oily gunk on your feet that would sting a little bit and feel cold. Who is this wife, and why should we believe this anecdote from an anonymous person? There's no way to remove regression to the mean as an explanation to this, but by now I'm suspecting this wife with a cough is mainly mythical>

If you have grandchildren, pass this on. <so presumably you don't need to bother if you're simply a parent, only if you're a grandparent?> If you end up sick, try it yourself and you will be absolutely amazed at how it works! <Actually, I suspect I'll just feel a bit silly. And will have minty-smelling feet>"

So of course I have done a search for the evidence and claims included in the post and have found a grand total of Nothing At All. I will say this though: If I was the manufacturer of Vicks, and someone had done some studies which found my product to be 100% effective, I would sing it loudly from every rooftop I could find. I would be the manufacturer of The Number One Most Effective Medical Product In The World Ever, and I would make sure that I made my millions on the back of that fact, as well as collecting my Nobel prize for Medicine and probably world peace as well. What I probably wouldn't do is ignore the claims, and continue on selling my product and advising that its used in a way which has a less than 100% chance of it working.

Direct harms from following this advice could include dermatitis and skin reactions. Indirect harms? Well, you've slathered some slippery, oily unguent onto the bottom of your feet. When you take your socks off, you may be slip-sliding all over the place.

The moral of the story is:Very rarely should you believe anything posted on Facebook. Unless its me, posting a link to my blog, of course.


UPDATE: I get a LOT of hits on this blog because of this post. If you've stumbled across it, i would love to know whether it has had any impact on what you thought about whether putting Vicks on your Feet would work, so please do leave a comment or drop me an e-mail.