2. MedlinePlus Medical Encyclopedia: Headache
When a headache occurs, write down the date and time the headache began, what you ate for the past 24 hours, how long you slept the night before, what you were doing and thinking about just before the headache started, any stress in your life,...
http://www.nlm.nih.gov/medlineplus/ency/article/003024.htm

3. Karine's Chiari Page
At that time of my diagnosis, I was suffering from headaches, dizziness, nausea, and vomiting. A few months before my ablation, my headaches became worse and they were occurring more frequently. I am now 22 years old and am in the process of...
http://www.angelfire.com/hi3/teenchiaripage/index.html

4. Argentina Handbook Health
The body should adapt itself to the oxygen shortage after a few days, although if the discomfort continues or gets worse (headache not yielding to aspirin, repeated vomiting, staggering and confusion), you must descend in altitude to prevent the...
http://argentina.gotolatin.com/eng/Info/Hbook/health.asp