Suddafed and Nitrox... bad combo?

[rox@ucf11]

I have heard that nitrox and suddafed can be a bad combination after researching it I found that suddafed is considered a CNS(central nervous system) enhancing or stimulant drug, coupled with CNS oxygen toxicity it was said although no tests have been done that the possibility exists that diving nitrox with a ppo2 over 1.4 adds a significant risk anyone ever heard of an instance where this was a problem? and does anyone know if there has been any tests done recently?

I am currently foregoing nitrox for my dive on monday untill I get more info on this issue because I will be taking suddafed and may be diving at or more than a PPO2 of 1.4.

[setesh]

This thread from ScubaBoard is informative. I tried looking up the article referenced on DAN's site, but they are having technical difficulties. If you are a DAN member, you can access all their stuff online for free, tons of info on there.

Nitrox and Sudafed - ScubaBoard

[Goober]

Originally Posted by rox@ucf11

I have heard that nitrox and suddafed can be a bad combination after researching it I found that suddafed is considered a CNS(central nervous system) enhancing or stimulant drug, coupled with CNS oxygen toxicity it was said although no tests have been done that the possibility exists that diving nitrox with a ppo2 over 1.4 adds a significant risk anyone ever heard of an instance where this was a problem? and does anyone know if there has been any tests done recently?

I am currently foregoing nitrox for my dive on monday untill I get more info on this issue because I will be taking suddafed and may be diving at or more than a PPO2 of 1.4.

If there is a congestion problem (possible sinus)that you are trying to address by taking Pseudoephedrine, I'm not sure it is a good idea to be diving period. I hear of people doing it true enough. I was strongly advised against anything such as this in OW as well as by divers since. I just don't think it is the "wise" thing to do. Now as far as how it reacts while you are breathing Nitrox, I'm totally ignorant. We can certainly try to find out for you though.

[wgt]

Originally Posted by rox@ucf11

I have heard that nitrox and suddafed can be a bad combination after researching it I found that suddafed is considered a CNS(central nervous system) enhancing or stimulant drug, coupled with CNS oxygen toxicity it was said although no tests have been done that the possibility exists that diving nitrox with a ppo2 over 1.4 adds a significant risk anyone ever heard of an instance where this was a problem? and does anyone know if there has been any tests done recently?

I am currently foregoing nitrox for my dive on monday untill I get more info on this issue because I will be taking suddafed and may be diving at or more than a PPO2 of 1.4.

Observations related to interactions between pressurized oxygen and many substances (including stimulants like pseudoephedrine) often stem from the clinical realm, but more controlled and systematic observations have also been made in hyperbaric chambers with both human and non-human subjects. As a general rule, substances that facilitate the production of oxygen free radicals increase susceptibility to the toxic effects of oxygen (e.g., amphetamines, thyroid hormone, insulin, etc.). As scuba divers, we are most concerned with the toxic effects of these radical forms of oxygen on the brain, which can yield seizures, unconsciousness, and subsequent drowning in the aquatic environment.

Despite these principles, I have not been able to find a specific scientific assessment of pseudoephedrine in the context of oxygen toxicity. Nevertheless, the general principles that govern its expression unquestionably suggest increased vulnerability to the toxic effects of oxygen with pseudoephedrine. The question is, "Would the effect be sufficiently dramatic as to render a healthy diver vulnerable to oxygen toxicity at the rather conservative maximum operating depths observed by most persons breathing nitrox (maximal partial pressures of oxygen being 1.4 - 1.6 ATA)?"

My best guess at this question is that the answer is "no." I will emphasize that this is not just a guess but a hopeful one at that, as I have breached 1.6 ATA while carrying a load of pseudoephedrine on more than one occasion. Despite my hopefullness, I emphasize that my answer assumed a healthy diver. Susceptibility to oxygen-induced seizures may be considerably heightened by many factors, including latent epilepsy (i.e., an unnoticed/undiagnosed seizure disorder).

The foregoing notwithstanding, the more important question is, "What do I do with the information?" My approach is simple. I counter heightened risks of oxygen toxicity (e.g., a dive with a partial pressure of oxygen of 1.6 ATA -- with or without pseudoephedrine) with substances that reduce the probability of expressing oxygen toxicity.

Antioxidant substances (e.g., vitamins C and E) are used in the clinic to reduce vulnerability to seizures in patients exposed to oxygen at high partial pressures. A shot of orange juice and a vitamin E capsule (available at Walmart) would certainly be predicted to nudge the safety margin in the right direction, noting that neither this nor other practical measures provide a license to exceed recommended maximum operating depths.

You have asked an excellent question.

[mpd525]

Wow, that was a pretty good answer. Not to hijack, but i've been told to take benadryl a day out from diving to help open up the eustacian tubes, and help open up the sinuses, is that true, or is there a specific drug to take to do that without harm?

[JugglingMonkeys]

Great answer wgt! Very useful.

Realistically many divers do take, and will continue to take, Sudafed.

You have provided much practical information. thanks

[setesh]

Thanks for the excellent information wgt!

I have really bad allergies, so I have taken sudafed before every dive, but I will be sure to take C & E with breakfast from now on. C & E will also help your body cope with the rigors of strenuous exercise; so it looks like they should definitely be a part of every dive day.

Something I have also found helpful is the NeilMed sinus rinse kits. You can get them at WalMart, Walgreens, CVS, etc. and they make a huge difference for me. I have seen a lot of people on SB mention that it has helped them too.

[rox@ucf11]

I will have to look into that setesh because my sinuses can be a problem

[cummings66]

Mine are a problem and I take pseudophed when I'm not diving Nitrox. When using that blend I make a point to not use it, DAN's article gave me enough information to believe that it might tip the scales towards having problems. Why risk it.

As to diving and using pseudophed to help with sinus problems, many of us do so and I for one am in that camp. I use 12 hour and take it starting a day out from diving and insure I take a pill a couple hours before the dive.

If I was to wait until my sinuses are clear I'd never leave the house. I do have limits as to how bad I can be before I call a dive, normal for me and I dive, if it's worse and I think I have a cold or something coming on I'll call the dive.

For example I called todays dive, I thought I could do it but was having issues clearing my right ear on the surface and could feel pressure that's not normal for me. I think you've got to base it on what your body considers normal.

[RECDiver]

Interesting. I have been diving with Nitrox and Sudafed since 1995, with EAN mixes of up to 50%. I stopped keeping track at the number of EAN dives after I reached 500 EAN dives, which was at least 4 years ago. I've never had an issue at all.