So, Here's a wonderful lady I nursed through adrenal fatigue as part of my adrenal fatigue and hypothyroidism study. She has recovered from adrenal fatigue and is back hiking.
After training again she recently summited Mount Whitney in the US, with a summit height of 14,505ft.
I think you can say that's a pretty good cure for someone who was truly incapacitated.

Just before she went she asked about altitude sickness. Is there a homeopathic remedy? And I told her she could use coca [just like the Peruvians do] ... but use it in homeopathic potency. That is seriously easy to carry!
In the USA you can order it from www.sourcehomeopathy.com. In the UK you can order from www.helios.co.uk.
Get them to suggest what potency you might need, but I think I recommended Sarah a simple 30c or 200c. With 30c you take a bit more often. With 200c you space about 1 hour apart and stop when you feel better. You can take a top up dose a few times a day to ward off altitude sickness if you are up there for long.
Use precautions though! Don't use this to push yourself into a place of danger. Keep an eye on how you are feeling and have a contingency plan. All the usual climbers safety rules!

Here, you get to see Sarah celebrating just before summiting ... letting me know that she did well with the coca.

https://youtu.be/G5aOJOb8bm0