Cold medicines increase DCS likelihood?

[21isfun]

I keep hearing people mention increased incidences of DCS when people are taking cold medicines. Is this really the case? And if so, which drugs (scientific/generic name is preferable) are the suspected culprits? I'd love to know the hypothesized mechanism for the increased DCS incidence in relation to the drugs as well.

PS- a sidenote- Also interested because I like to take sudafed for a few days prior to diving trips as my ear/nose/throat have decided they hate me, and I always end up stuffy after long plane trips!

 

[AzAtty]

Years ago there was a report concerning the use of non-steroidal anti-inflammatory drugs (NSAIDs, which may occur in some decongestants) in connection with TREATMENT of DCS. The theory behind the treatment, as I understand it, is that secondary tissue damage is caused by inflammation, and NSAIDs were hypothesized to alleviate some of those symptoms. Keep in mind, though, that the NSAIDs were administered after recompression therapy.

Studies have been done concerning the effects of psuedoephedrine on a diver, but until drugs dosages were five to ten times the norm, no impairment was noted. The abstract of that study did not indicate that the researchers were concerned about DCS. Understand that we really don't KNOW as much as we'd like about the causes and effects of DCS (other than decompressing); we *THINK* we have some good ideas about it. So it is entirely possible that cold medication can contribute to DCS, but we simply do not know (as far as I know) what it does.

Another possibility is that the speakers have inadvertently mistaken DCS for oxygen toxicity. Some chemicals are believed/known to increase susceptibility to O2 toxicity, and diving high O2 concentrations while on cold medicine is generally considered a bad thing.

Of course, my doctorate is not in medicine, so don't take anything I say as gospel. And I'd be thrilled for a medical doctor to educate us on this point.

 

[DocVikingo]

Here's the beginnings of a sound education on the issues:

DAN Divers Alert Network : Pseudoephedrine & Enriched-Air Diving?

Regards,

DocVikingo

 

[AzAtty]

Thanks for the link, Doc. Are you aware of any studies concerning correlation between decongestants and decompression sickness?

 

[DocVikingo]

Hi AzAty,

Here's an abstract of a pretty good study:

Rubicon Research Repository: Item 123456789/4117

The results are consistent with DAN's conclusions under the "What's the bottom line?" section linked in my original response.

Helpful?

Regards,

DocVikingo

 

[AzAtty]

Actually, that was the abstract I was thinking of when I mentioned studies related to psuedoephedrine. It would be nice if the article could be accessed through Rubicon, but it appears they only have the abstract on file.

I think the OP was interested in whether cold medication affects susceptibility to the bends, and I didn't originally divine anything from the abstract related to bends specifically. From the abstract, the study referenced seemed to be concerned with toxicity and impairment relating to the drugs while exposed to hyperbaric conditions, as did the DAN study.

 

[21isfun]

ok- so from what I am gathering- if I'm not diving EAN-just normal air-the occasional sudafed for congestion should be fine since I've never had an adverse reaction to it in the several years I have used it.

Thanks everyone for all the help!

 

[AzAtty]

Well...let's qualify that statement a bit. From what Doc has cited (and from what I understand), there is no evidence that pseudoephedrine predisposes one to decompression sickness. That's a far cry from saying it's OK to dive while taking a decongestant. Should the decongestant wear off at depth, you might find yourself with barotrauma in the ears, sinuses, and lungs. Therefore, we discourage diving while taking decongestants.

 

[Damselfish]

because of the possibility of the stuff wearing off at the wrong time, if you're going to take it I suggest sticking to the 12 or 24 hour versions. I prefer the 12 hour version.

 

[DocVikingo]

AzAtty is spot on here and Damselfish makes a good recommendation.

Thanks guys.

Regards

Doc