8 hours is a lot of flying time. Flying direct is always important, unless you can manage to break up a long trip and recover for at least a few days. I find travel by boat much, much easier. Consider your options next time.

Like Catra I do most of the things she suggested, but I do check luggage because it's too difficult for me to manage. You can always find a porter if you're travelling alone to help. I've been known to box up items and mail them home to avoid heavy luggage on the return trip. You can also learn to travel much lighter than you might expect.

If you respond well to steroids, consider starting a pack a few days before flying, it can make the difference of needing a few days of recovery as opposed to a week or more. The last few times I flew I also picked up the flu, and would recommend extra vitamin C and perhaps echinicea and golden seal if you react well to them--we do have compromised immune systems.

I try and swim within a day of landing, it really does help.

If you respond well to massage, you might want to undergo one before and/or after landing.

In all honesty, travel used to be very important to me. At some point, it stopped being so.

If you're needing to travel for medical care, you might want to really explore closer options, different treatment, or consider relocating.