Altitude sickness is caused due to rapid ascent to higher due to the decreasing amount of oxygen that occurs at high altitudes. For severe symptoms person should see a doctor as soon as possible. While waiting for medical help kindly follow these first aid tips.
give oxygen, if possible
ensure person is kept warm and well rested
plenty of liquids recommended
an ibuprofen may work for headache
Seek medical help, if:
symptoms are severe
mild symptoms persist after being back on plains