Sudafed / Pseudoephedrine & Diving (on air)

[KrisB]

Ok, first off, this is not a troll. I did a search and could not find anything concrete about it here, or on DAN's site... so it made sense to start a thread that could encompass it all.

The question is thus: what is the general feeling on Sudafed (generic name Pseudoephedrine HCl) and diving on air (21% O2)?

I have found the following:

* Sudafed and EAN (Nitrox) is strongly cautioned against (by DAN, PADI and perhaps others), due to a potential increased risk of CNS toxicity.
* Sudafed and air seem to be accepted by DAN
* any medicine and diving seems to be cautioned against by most training agencies.

Please post opinions, facts, experiences and other useful comments here, but do try to keep the information relevant.

Thanks,

 

[BHB ScubaTroll]

Ok, first off, this is not a troll. I did a search and could not find anything concrete about it here, or on DAN's site... so it made sense to start a thread that could encompass it all.

The question is thus: what is the general feeling on Sudafed (generic name Pseudoephedrine HCl) and diving on air (21% O2)?

I have found the following:

* Sudafed and EAN (Nitrox) is strongly cautioned against (by DAN, PADI and perhaps others), due to a potential increased risk of CNS toxicity.
* Sudafed and air seem to be accepted by DAN
* any medicine and diving seems to be cautioned against by most training agencies.

Please post opinions, facts, experiences and other useful comments here, but do try to keep the information relevant.

Thanks,

Way back when (makes it seem like I know what I am talking about) I was working toward instructor, we used to take 4-6 of them on chilly nights before a dive... just to be sure we didn't have squeeze in the morning.

Today, buy more than three boxes and turn 'em into Crack!
---
I have not heard anything about today's medical practices concerning the little red pills (But, I also haven't looked for today's medical practices on the subject)

Over Easter, my son had a heck of a time with ear squeeze. After the boat landed, I went right to Walgreens and bought a pack. Next day.. no problems with sinus

 

[Halthron]

I take Pseudoephedrine (120mg 12-hour) every dive day; I also use Nitrox. I don't consider this a problem because while I understand the concern, I also know how to follow the CNS tables and knock a bit off because I'm taking it.

You need to understand that Nitrox isn't the problem, it's the partial pressure of the oxygen in use that determines the effect. Thus, 40% nitrox at 66ft is safer in terms of CNS than air at 165ft. The Pseudoephedrine supposedly just reduces the level you will have problems with CNS at.

 

[KrisB]

I take Pseudoephedrine (120mg 12-hour) every dive day; I also use Nitrox. I don't consider this a problem because while I understand the concern, I also know how to follow the CNS tables and knock a bit off because I'm taking it.

You need to understand that Nitrox isn't the problem, it's the partial pressure of the oxygen in use that determines the effect. Thus, 40% nitrox at 66ft is safer in terms of CNS than air at 165ft. The Pseudoephedrine supposedly just reduces the level you will have problems with CNS at.

Perhaps I should clarify my question so as to hopefully better answer other people's questions.

The premise of this is that we're diving air (21% O2) within Recreational Dive Limits.

 

[MoonWrasse]

Ok, first off, this is not a troll. I did a search and could not find anything concrete about it here, or on DAN's site... so it made sense to start a thread that could encompass it all.

The question is thus: what is the general feeling on Sudafed (generic name Pseudoephedrine HCl) and diving on air (21% O2)?

I have found the following:

* Sudafed and EAN (Nitrox) is strongly cautioned against (by DAN, PADI and perhaps others), due to a potential increased risk of CNS toxicity.
* Sudafed and air seem to be accepted by DAN
* any medicine and diving seems to be cautioned against by most training agencies.

Please post opinions, facts, experiences and other useful comments here, but do try to keep the information relevant.

Thanks,

Diving's dirty little secret.

Sudafed usage while diving can cause some problems:
- Reverse block if it wears off UW.
- Impaired mental state.
- Dehydration, contributing to DCS.

Additionally some people are predisposed to tachycardia, as a reaction to the sudafed. You really don't want to dive under such a circumstance, IMO.

 

[riguerin]

Perhaps I should clarify my question so as to hopefully better answer other people's questions.

The premise of this is that we're diving air (21% O2) within Recreational Dive Limits.

I'm by no means a medical expert nor an authority on this topic. However, I would guess that the increased risk of CNS due to Pseudoephedrine HCl is a function of your actual O2 exposure. It's very difficult to even approach an O2 exposure limit while diving 21% within recreational limits.

Using 21% O2 and a conservative PPO2 of 1.4, the MOD is 187ft. The recommended recreational depth limit of 140 ft, is well above this depth.

Therefore, doing a dive to the maximum recreational depth limit of 140 ft on 21% would yield a PPO2 of 1.1. If this dive was executed to the NDL of 8 min (using DSAT tables), then the O2 exposure would be less than 5% of the daily maximum allowable. Alternately, at the other end of the spectrum, a dive to 35ft on 21% would yield a PPO2 of .43 (need to round up to .6 for DSAT table). Assuming you had enough gas to do this dive to the NDL of 205 min, then the O2 exposure would be less than 30% of the daily maximum allowable.

 

[Halthron]

Perhaps I should clarify my question so as to hopefully better answer other people's questions.

The premise of this is that we're diving air (21% O2) within Recreational Dive Limits.

From a CNS perspective, Nitrox 32 at 50ft is safer than air is at 100ft. Of course, both are in the "negligible" range for CNS at those depths. The point (and I'm not a doc) is that Pseudoephedrine shouldn't be used at high partial pressures of oxygen, which are usually only found using Nitrox when staying inside rec depths. That doesn't mean Nitrox can't be used.

 

[Cacia]

Unless I am mistaken there is some question regarding the lowering of the seizure threshold. If that is the case, the partial pressure that is dangerous could be lower.

I was under the impression this was not all clearly worked out yet...

Anyway, the formulation, at least here in Hawaii has changed to phenelephrine. The old formulation is "behind the counter" at least for awhile. (due to the popular conversion to meth)

The reason I do not like this drug for diving is that it causes some vasoconstriction (can raise your BP) and also causes tachycardia in many people. (sympathomimetic)
With so many diving deaths resulting from heart attacks, it seems like a bad idea to me. Personally, I had several very bad reactions to it where my heart raced while diving, before I figured it out. I am pretty casual about having a beer with lunch...maybe diving later that day, etc., but this medication seems dangerous to me for it's cardiovascular effects. The seizure threshold effects, I think are suspect.

On the other hand many people take it and dive, I just wonder if the fact they took it goes overlooked once they have an event, like a heart attack.

 

[MoonWrasse]

I'd add that if the reason for taking the med is nasal stuffiness, and problems equalizing rather than sinus/cold, use the saline up the nose method as it works better IMO and lacks the noted side effets.

 

[KrisB]

this is all good information, guys (and girls)... keep it coming.

As I said, I have had trouble finding any discussion or research on it when I tried earlier.

Even the top hits on Google were insisting that I *must* have been thinking of Sudafed and Nitrox!