Flight attendants have been known to hand over an entire bottle to a thirsty passenger, even in coach. Carrying a spray bottle to spritz on your face and body will also quench parched skin. Hypoxia or low oxygen levels in the blood caused by altitude or low air pressure is another one of the things that makes you feel crappy when you hit the ground. To counter it you should drink carrot juice, or eat lots of raw carrot, two to three days before flying and while you are in the air. Carrots help your blood retain oxygen better to alleviate the side effect of the low air pressure in the cabin.
Many airlines literally put on airs , providing first and business classes with fresher air.
In an effort to save money, crafts sometimes re-circulate old air in economy, but will usually crank up the new stuff if requested to do so. If you've experienced this, you know that trying to put shoes back on at the end of a flight can be a harrowing task as your feet have mysteriously transformed into two swollen daikon . To avoid this feeling, order the airline's low sodium meal or, better still, pack your own snacks. Partying or not sleeping the night before departure is also another no-no. If you're feeling rested and refreshed before you take off, you'll feel less of a lag when you de-plane.