Ditch the Dimetapp?

I just finished up the teaching part of my teaching fellowship.  I got to teach five weeks of an undergrad organic class, and I had a blast!  As the seasons started to change, though, I started to hear more and more coughing and sneezing and sniffling.  Everyone's all concerned with the swine flu, but we're also entering cough and cold season, too.

The news I'm presenting today from ScienceDaily is old news, but I hadn't heard it before... That makes it news to me   In an article published in 2004 in the journal Pediatrics (DOI: 10.1542/peds.114.1.e85), Dr. Ian Paul of Penn State Children's Hospital studied the effect of dextromethorphan and diphenhydramine versus placebo in providing nighttime relief from cough symptoms as a result of upper respiratory infection.

Dextromethorphan is sold as an antitussive (cough medicine) in just about every cough formulation known to man.  The study specifically tested cough syrups in children ages 2-18.  Parents were given a survey to used to rate severity of symptoms.  The following morning, parents filled out a second survey re-rating the same symptoms.  The follow up survey also asked how both the children and parents slept during the night.

The double blind study showed that while symptoms did improve with the active ingredients, there was no statistical improvement over placebo.  On the scoring scale used in the study, children taking dextromethorphan improved 10.06 points, while those taking diphenhydramine improved an average of 11.79 points.  By comparison, children in the placebo group improved 10.85 points.

Given that dextromethorphan can easily be abused when taken in high doses, one wonders whether a spoonful of sugar (in the form of honey) might be as good of a cough syrup as any.  Keep this in mind when you browse the shelf at the drug store this winter.

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7 Responses to “Ditch the Dimetapp?”

1. 1
   Chemgeek @ November 22, 2009 at 6:33 pm

   I use honey for my kids all the time. It doesn't do anything, but they don't know that. It does provide some level of comfort.

   I've also done a number of 'experiments' with them. I count how many times they cough during a 15 minute period and then do that same after giving them a spoonful of honey. There has never been a change in their cough, but they tell me they feel better.

   So, is relying on the placebo effect dishonest?

   Reply
2. 2
   chiraljones @ November 22, 2009 at 8:16 pm

   first thing I immediately noticed about the study that may affect the data: having parents rate the severity of the symptoms of their kids, rather than the kids rate the symptoms themselves.

   could that evoke some sort of "placebo-by-proxy" effect?

   Reply
3. 3
   mitch @ November 23, 2009 at 12:29 am

   I wish there was a scientific way to see if there was a difference. A parental survey seems lacking.

   Reply
4. 4
   Chemjobber @ November 23, 2009 at 9:20 am

   Wouldn't a Chemgeek-type digital solution work the best? Digitally record the child's nighttime sleep patterns, get some poor psych-major to count the number of coughs, presto - believable data!

   Reply
5. 5
   azmanam @ November 23, 2009 at 2:18 pm

   The authors seem to be saying 'hey, your cough's going to get better with time.' The cough syrups never claim to 'cure' a cough - only to relieve symptoms. Given a night to rest (and allow time to elapse), children taking cough medicine improved the same as children taking placebo.

   I'm sure there's a placebo-by-proxy effect, but might that just confirm the findings? Whether or not cough medicines actually work (and the authors appear to think they don't), parents of children on the placebo felt their children improved just as much as parents of children on active ingredient. Given that the cough medicine isn't going to cure a cough, all that you're really aiming for when taking cough syrup is relief from symptoms. If a placebo can do it for the price of sugar (literally), then why risk the side effects/potential abuse issues of dextromethorphan.

   Interestingly, as I was reading about DXM and related abuse, one site I read indicated that cough syrups taste terrible on purpose. For two reasons. One, it helps mask the already terrible taste of the alkaloid DXM, and it provides a negative feedback to hopefully stave off potential abuse. It's not that they can't make it taste good, it's that they're actively trying to KEEP it from tasting good.

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6. 6
   mitch @ November 23, 2009 at 5:59 pm

   I like the taste of medicine though. IT is probably why I like root beer.

   Reply
7. 7
   azmanam @ November 24, 2009 at 5:42 am

   Did anyone watch House last night?

   Reply