Mt Whitney Zone Forums General Discussion Diamox for AMS (altitude sickness)

The Mt Whitney "group" on that infernal social media site has a good discussion on Diamox and AMS, started by wbtravis when he posted a link to his blog.

WBTravis:
April 16 at 8:35am

replies:

Christine O: Since I get Migraines and have Raynaud’s, I'm always a little leary about taking things that might cause headaches and mess with my circulation. Too many hikes planned for the summer to get stuck with altitude sickness so I'll be checking into it

Steve E: I struggle with altitude sickness, and Diamox worked wonders for me on Whitney

Scott G: That's a photo of White Mountain Peak. It's a good 14er warm up for Mt Whitney.

William K: That's White Mountain in June, which makes it a good early season trip...especially this year after a dry winter.

John M: How likely is it that a Dr would Rx that for you? I've been looking into it for Whitney this year since were coming from 2 blocks from the beach in SD and only have one night to acclimate.

Scott G: I would take diamox if you haven't been to altitude before. It helps. I took it when I did MT Kilimanjaro.

April Y: John M, any dr. can prescribe Diamox however they will prescribe the recommended dosage by the manufacturer. It is WAY too much. You need to find a dr. who understands & is knowledgeable in high altitude medicine. I cannot recommend to you the dosage that works for me but it worked for me on a training hike on Mt. Dana (13k') and on my actual climb on The Grand Tetons. I suffer fm AMS horribly and it always hits me at 12k' predictably. W/Diamox, I slept and ate so well on The Tetons where everyone around me felt like crap. I have attempted Whitney 5X thru MR and wished I knew about Diamox sooner.

John M: Good to know. I just ask because I'm not to sure about marching into my Dr office and asking for it. I've heard lots of people who have been turned down by their doctors.

April Y: Diamox is a diuretic so I suppose you should be careful if you have a heart condition or have high blood pressure. I have hypertension (take meds regularly) but was careful in taking the Diamox first at sea level before going up high. It didn't affect me adversely. I will let you know a side effect that is weird but benign is random buzzy feeling in your palms, soles of your feet and ears. For me, the symptoms were isolated to one extremity, went away and then would transfer to another. It wasn't constant, came and went. Didn't effect my energy level nor hindered me physically. I have heard others experience this as well.

Nancy F: There were 4 of us who climbed Whitney a couple of years ago, and I read the Whitney blog like the Bible. Many hikers SWORE by diamox so we all had it prescribed, used it at its lowest dose a few months before we went to make sure that there were no side effects and ALL of us had NO issues with altitude on the climb...other than the normal lack of oxygen near the summit and needing to slow down more frequently. Let me add that the youngest in our group was 53. The next time I find myself attempting a hike over 12,000' I will take diamox.

William K: John, Most doctors will prescribe it...at least that the sense I get reading the Whitney boards over the years. The problem, like April said, is getting the dosing right...and it is personal (my dose regiment differs from current recommendations). This is why I tell people to search out Dr. Peter Hackett in my blog posting and not post how I take it. Hackett is the go to guy on how to dose Diamox. I only post how my personal doctor told me to take it and the results. I do not recommend this drug to anyone unless they have experienced the debilitating symptoms of AMS because the side effects can end your trip before it starts. Again, do White Mountain, see if you have problems, if you do, see your doctor. There are no short cuts.

Joseph Q: this is a great topic to talk about. I agree most docs will prescribe. I did mine by phone and his only question was how long I would be at altitude. I also took less than prescribed. Interactions with other drugs is a concern though and should be researched. Any ideas on that?

William K: Joe, That is a question for a pharmacist. I take statins and it does not have an interaction with it.

Steve C: People are beating around the bush here on the dosage. If you get a prescription and it says take 250 mg twice a day, don't do it! For hiking, half that dose should be the max, and I have seen many who say a quarter dose works for them. Diamox now comes in 125 mg tablets, and they can be cut in half for a 62.5 mg dose. That is what I would take twice a day.

Diamox was originally created and prescribed for Glaucoma, and 500 mg doses were prescribed. I've had the buzzing fingers once on the low dose, can't imagine what it would be like with that huge amount.

I am wondering if anyone has considered or used Diamox for altitude symptoms other than AMS: wind, shortness of breath, endurance, appetite, sleep etc. For me this is an important difference: acclimation for avoiding AMS vs acclimation for more normal or typical responses such as shortness of breath and endurance.

Its important to me because I have never had AMS, but I have always struggled with what I call general acclimation. It just takes me a long time to get my breath at elevation.

Until my JMT TH last year I had never fully acclimated to elevations of even 7500-8500 ft in less than a week. And I had also never really done a high elevation trip without spending at least that amount of time at elevation, so quick acclimation was never an issue.

As I approached my JMT hike, I realized that this was the first time I would be faced with having no time to acclimate before plunging into a 6000 foot vertical start, from YV to Cathedral Pass. The trip of a lifetime, I might add (seriously, until last year, JMT through-hike was my entire bucket list)

Oops.

AHA! thinks I: DIAMOX! In theory, it stimulates the entire acclimation process, which should include the haemoglobin/O2 thing that makes up for low 02 at altitude, which manifests in things other than AMS, like getting winded by tying your shoes or walking up half a flight of stairs to the dining hall, right? So, even though I don't need it for AMS, it should still work for what I call GENERAL acclimation.

So, I started on the 2x125 mg/D Diamox regimen two days before hitting the TH at Happy Isles, three days before crossing above 6000 feet (LYV) and four days before reaching 8500 ft (Sunrise). Five days before hitting Cathedral at 9700 ( according to my map, you actually top out at 10k before the pass).
That's some serious elevation gain in the first couple of days.

If Diamox can knock out AMS, it ought to be able to take the edge right off that elevation gain, right?

AS far as I could tell, the Diamox did not one damn thing for my GENERAL acclimation. I had been training for a year, and could do 15 minute miles carrying 40 lbs at sea level all day long by the time I hit the TH. That was my training regimen. So if I had endurance problems it was not my general conditioning: I took that out of the equation. The only variable was elevation.

On the actual trail, I did not feel anything like my sea level conditioning until 6 days in, leaving Red's, and never actually matched that 4 mph pace until days after that.

SO, this leaves me wondering: if the mechanism of Diamox is to induce the acclimation process, why does it seem to ward off AMS but not have any effect on other acclimation factors? Or does it?

Harvey, are you reading?

Salty Dog, here's my non-medical opinion... Being able to cruise along at altitude like you do at sea level, I think, is all about hemoglobin levels. How much oxygen your lungs can absorb from one breath, and how well it can be transported to the muscles. I think that is why it took you (what... week and a half, maybe two?) so long to reach the level of ability that you desired. I don't think Diamox would help even a tiny bit in that area. On the other hand, I think your training did help, even at sea level.

The other part of AMS, the headache, lack of appetite, and nausea are not well understood. Researchers can't identify what is happening inside our bodies that cause that.

I am guessing it is right down to the cellular level, but the changes are so miniscule on that level that nobody can tell what the problems are. Somehow Diamox helps that situation a bit.

Diamox has worked for me for general acclimation heading from sea level to 10,000 ft range with little or no time to adjust. I usually start to get a headache and shortness of breath around 9,500 ft or so, but with diamox I feel much better than usual, but still not 100% by any means. Not sure if that qualifies as "general acclimation" but seems like what you're talking about.

I was concerned about the side effects, but never had any issues with the 125 mg 2x/day dosage. I start the day before and taper off within a few days on longer trips. I've tried Ginko Biloba a few times, but it didn't seem to help much. That's my $0.02, keep the change. Your mileage may vary (YMMV).

Yes: my understanding is that getting your wind back is about hemoglobin and oxygen, but I was also under the impression that the mechanism of Diamox is the same as what triggers that part of acclimation. I no longer think that is the case. As a matter of fact, it took 5 days before I was not struggling by mid afternoon and 10 before I was kicking ass at my sea level pace. About the same as I remember from going to summer camp, where the first high country backpack trips were after about 10 days of day hiking at 7800-8500.

But my conclusion is the same as yours: Diamox may help with AMS, but it does not apparently accelerate general acclimation/acclimatization. I will definitely take this into account on my next High Sierra trip: just get in shape get above 6000 or so ASAP, and take it easy for the first couple of days. that's why I love the High Sierra Trail: it starts at abut 6700 and only goes to 8300 in the first 18 miles or so, before up and over Kaweah Gap. As opposed to either the Whitney or Yos end of the JMT, where there is no avoiding a steep start.