As I have said before, if you are going to be hiking at high elevation please take a can of oxygen with you . The cans weigh next to nothing and contain enough oxy to relieve the symptoms, and can be purchased on Amazon.
What kind of height are you talking about here.
Luke, watching your Part 1 tips for backpacking, I feel like I need to issue a warning to you and other individuals that spend as much time in the out of doors as you do. I am an optometrist and am an avid backpacker as well. Do realize that the sunglasses you are wearing offer NO protection from the very harmful UVA and UVB sun rays that we all deal with every day, whether hiking or not. Yeah, the investment is going to be a lot more, but the retinal and corneal damage that can ensue over time is nonreversible. Just a thought. Get into some quality polarized lenses!