Sunday, November 21, 2010

Living High

Our first pass over 5,000 m (ever!) on
Day 3 of our Cordillera Real trek.
When Jan and I planned this trip, we wanted to be in the Andes, the second highest mountain range in the world. That meant we would be spending a lot of time in really high places. Working out an acclimatization process that would get us to be healthy while high would be key to our enjoyment.

So here are  a few tips for aspiring altitude travellers, gleaned from what has worked for us (of course, everyone reacts a little differently to high altitudes, so take this as food for thought):
    1. Take your time to acclimatize properly. We took 7 days with acclimatization hikes (ie hike high, sleep at 3,000 m), lots longer than any of the commercial trips offered in the Cordillera Blanca. They are set up to fit the typical 2 week vacation after all. 
    2. Take a tylanol if you get a headache. Diamox is a favourite drug to take to help people with altitude issues, but it is also a diuretic and as such counter-indicated for altitude issues. If you can take a few days to get used to being high then a tylanol is probably a fine option.
    3. Drink water. It is the best medicine against AMS symptoms. Naturally, do not over-hydrate. And until you acclimatize try to keep away from alcohol ... no fun, I know.
    4. Take responsibility for your health and don´t blame your tour operators or guides if you get AMS symptoms. Just because they offer a particular itinerary doesn´t mean you need to follow it. You kow yourself and you get to make sure you have a great time!
      Huayna Potosi in the late
      afternoon light of day 8. The next day
      we walked to Base camp around the
    5. Look at the elevation of specific treks and mountains you want to tackle and then plan your route. While the mountains in Peru´s Cordillera Blanca are a bit higher than in Bolivia´s Cordillera Real, the trekking is actually lower in Peru than in Bolivia! Make sure you understand the heights each trek/climb will get you to and then plan your itinerary accordingly!
    6. And take some time to understand the climate specific to the mountains you want to visit. We noticed that 4,400 m on Aconcagua is a totally different experience than 4,400 m in the Cordillera Blanca: Aconcagua is an arid desert while in Peru the tropical climate is far moister and animals graze up to 4,800 m! Guess which is easier on the human, then?!
In the Cordillera Blanca we slept between 3,600 m and 4,600 m. But in the Cordillera Real, we slept most nights at 4,700 m. The reason is that the Cordillera Real is sitting on top of Bolivia´s Altiplano (High Sierra) which is at 4,000 m! There is no low. Simple. This also means that the hiking in Peru covered a lot more elevation changes - we had 4 days with ascents of over 1,000 m - while the trekking in the Cordillera Real was "flatter"; we would ascend 600 or 700 m in a day. But all of our time was spent hiking between 4,500 m and 5,350 m.

This is the final path to the top of
Huayna Potosi. See the steps at the edge of
the snow and rocks? Just above that
was the summit. (Pedro´s head is here just for scale.)

So when you plan your trip, find out how high you will sleep, how high you will hike and how much elevation change you will cover. Then you can sort out the best plan for you.


  1. Wait - your tips said "No alcohol" what the...? I guess I will stick to the lower altitudes

  2. Thanks Inga for detailing the acclimatization process in high altitudes ... very interesting ! I am having lunch with Esther today. Cheers. Guy

  3. I´m intrigued by your idea that Diamox is "counter-indicated" against altitude sickness : this runs contrary both to my experience , and more importantly to all medical advice - see for example the CDC advisory at

  4. Thanks for your comments. Diamox always makes for interesting opinions. After all, medical intervention seems based on a "practice" and "opinion" by doctors.

    As I say in my post, I am sharing my personal experience being in Peru, Bolivia and Argentina. I do not speak about what works in other mountain ranges. I am encouraging readers to think about their altitude travel for themselves. I have purchased Diamox 2x before leaving Canada and neither time was it the solution to my needs. Following the advice by the local people/guides, acclimatizing over time and ensuring good hydration all have worked very well.

    Diuretic function suggests that more liquid intake is needed for proper hydration. As the symtoms of dehydration and AMS are rather the same, this makes me say what I did. Drugs can have side effects that can be undesirable. Diamox is no exception there.

    From our friends at Wikipedia here's a plain language explanation on how it works.

    "To reduce the incidence of Acute Mountain Sickness acetazolamide is sometimes taken prophylactically, anywhere between 125 milligrams (mg) to 1000 mg per day,[9][10] starting a few days before going to higher altitudes. Such use is recommended for those ascending from sea level to 3000 meters (9800 feet) in one day, or for those ascending more than 600 meters (2000 feet) per day once above an altitude of 2500 meters (8200 feet).[11][12] Also, prophylactic use is recommended for those with a significant history of acute mountain sickness.

    Acetazolamide forces the kidneys to excrete bicarbonate, the conjugate base of carbonic acid. By increasing the amount of bicarbonate excreted in the urine, the blood becomes more acidic. Acidifying the blood stimulates ventilation, which increases the amount of oxygen in the blood. At high altitudes, climbers hyperventilate in response to lower oxygen levels. The hyperventilation results in reduced carbon dioxide (an acid) and a respiratory alkalosis. The normal physiologic response to a respiratory alkalosis is for the kidneys to increase excretion of bicarbonate (a base) to compensate for the loss of carbon dioxide. This kidney response takes a few days, however acetazolamide in a sense accelerates this process by leading to a more rapid renal bicarbonate loss (metabolic acidosis).

    Note that acetazolamide is not an immediate fix for acute mountain sickness; it speeds up part of the acclimatization process which in turn helps to relieve symptoms. This may take up to a day or two, and requires waiting without any further rapid ascent. It is often advisable to descend if even mild acute mountain sickness is experienced. If serious sickness is encountered, descent to a lower elevation is considered to be mandatory unless other circumstances present greater danger."

  5. Diamox continued: The side effects listed on same Wikipedia article:

    "Everyone will experience more frequent urination as a result of using acetazolamide. One should drink more fluids than usual to prevent dehydration and headaches.

    Common side effects of using this drug include numbness and tingling in the fingers and toes, and taste alterations (parageusia), especially for carbonated drinks. Some may also experience blurred vision but this usually disappears shortly after stopping the medication.

    Acetazolamide also increases the risk of developing calcium oxalate and calcium phosphate kidney stones. Acetazolamide prolongs the effects of amphetamines and related drugs. Acetazolamide also causes metabolic acidosis."

  6. Sorry , but there are a lot of misconceptions here , starting with the idea that medical guidelines are based on vague opinions and practice. The guidelines from CDC and ISMM ( ) etc are evidende based , and there are decades of systematic experience behind the Diamox recommendations. This is clearly shown in the CDC references , like in the WEM document .Another example is when gingko got a lot of attention a few years back : there were several studies with made with around one housand participants , that made double blind comparisons between the effect of Diamox , placebo and gingko. A recent french study ( Richalet et al ) had three thousand plus participants from the Himalayas , Andes and the alps over two decades , and also consistently showed that those on Diamox came out better .

    The wikipedia article ( I´m one of the contributors btw ) is not one of the best examples of commitee writing : much of what is mentioned is off not by being wrong ( well the drug doses mentioned are definitely off ) but out of context .Use bona fide medical sources , national health guidelines first. Frequent urination and metabolic alkalosis for example is exactly the same thing happening in natural acclimatization : it´s a desired , not side effect.

    Water lastly is one of the "medicines" that needs to be dosed right : “Forced” or “over”-hydration has also never been shown to prevent altitude illness and may even increase the risk of hyponatremia.." ( from the WEM document" ... and hyponatremia is a potentially lethal condition , that gives exactly the same effects as advanced altitude sickness ( see , or the warning from Himalayan Rescue Association ) , cerebral and other edema that causes nausea , headaches or a lot worse. Dosing right also means avoiding dehydration , but this does not mean adding liters of plain water. On that path lies risks.

  7. Ooops - obviously meant metabolic acidosis above. makes this comment on "water therapy , calling it " Myth # 4 ": "Too much water is harmful and can dilute your body's sodium levels (hyponatremia) causing weakness, confusion, seizures, and coma." Google "wee for wii" for water intoxication at low altitude.

  8. Like I say, I am all for people gathering information - from a wide range of sources - and thinking for themselves.

  9. I would suggest relying first on medical sources ( none of which support the idea that Diamox is "counter-indicated " ) , and that free thinking against medical consensus needs some very solid arguments.

    Of course there are a number of situations where medication is overkill ( like multiday use in Sacred Valley ) , but inaction also has it´s price : sometimes the disease actually is worse than the cure. The side effects listed here is mostly copy pasted from the life long use in the normal application , glaucoma. You won´t develop kidney stones over a few days to a week use of Diamox , and you´ll find the list of all possible side effects for antibiotics will come out equally daunting . I see that you mention packing three different antibitics . Listing all possible side effects for quinolones like Cipro for example you would come up with , among others :

    * Phototoxic reactions
    * polyneuropathy
    * liver failure
    * heart rhytm change
    * anaphylactic chock (!)

    and a number of medicines that interact with Cipro.

    Also I can´t help noticing that your own travel doc doesn´t seem to agree with your view on Diamox : the fine medication mentioned in your Vacccines and Medication post should be Diamox :

    "We got prescriptions for a bunch of other fine medications as well as something to help with altitude sickness.."