I am from Haute-Savoie, a French department known for these mountains. You can find there the highest peak in western Europe, the Mont Blanc, which rises to 4809 meters. I admit, I sometimes take pride in being from this area, full of elegant peaks, and snowy summits. I imagine it is a bit like the people that take pride in belonging to a land of sailors. Mountain to me is one of the landscapes that I like and where I can feel at home.
Now we begin a part of the journey which will lead us to know some of the highest cities in the world: Cusco, Puño, La Paz … 3398, 3819, 3639 meters of altitude respectively. To compare, the highest village resort in Western Europe: Val Thorens is at 2300m altitude. The highest village (about thirty people live there) Juf in Switzerland is at 2124m.
We just landed in Cusco, more than 400,000 inhabitants living at 3400m. I do not suddenly feel so mountaineer… Especially as we plan to hike up to 5000 meters here (the rainbow mountain). Concretely for this walk, we will equip our hiking shoes “high mountain” in Gore tex with the interior filled with sheep hairs double thickness while the local guides who will accompany us will be equipped with sandals.
As you can see, we do a bit of yoyo with altitude.
And as we go beyond 2500m I checked a little bit about mountain sickness through the review: Acute high-altitude sickness. A “review” in science is a compilation of knowledge on a given subject. It avoids to someone simply curious about a specific subject (me) spending hours reading and trying to understand a multitude of scientific articles that are far from my original specialty.
In summary, the fact of being at high altitude and therefore at a lower barometric pressure reduces the quantity of oxygen available at each inspiration. The body needs time to acclimatize to this change.
Also if you arrive in Cusco by air without prior acclimatization you have almost 50% chance of knowing the high-altitude sickness. Symptoms are a headache, insomnia, nausea or dizziness. To prevent it: spend 2 nights or more in altitude in the 30 days before the trip (this was our case in Bogotá, rest the first 48 hours on arrival.
Regarding local remedies (I think about the coca leaves offered in almost all Cusco hotels) so far no study has shown any preventive effect.