I am not sure of the altitude sickness. Is there any way to find out if I may have altitude sickness, if yes, what precautions can be taken to avoid it on the trail?
If you don't live near high mountains for training hikes, then it is likely that you will suffer from altitude sickness with loss of appetite, nausea and headaches. Here are some steps that you can take to minimize the chance of illness.
1. Take the herbal supplement ginkgo biloba for about a week before your hike. You can find it in the vitamin section of any grocery or drugstore. Follow the directions on the label. Several clinical studies show it helps with altitude sickness.
2. Arrive in Lone Pine a few days early and spend time at altitude. You can hike the trail as far as Lone Pine Lake without a permit. A paved road leads to nearby Horseshoe Meadow at 10,000 feet. A good dirt road leads to the Ancient Bristlecone Pine Forest at 11,000 feet. These places are worth seeing in their own right.
3. Take aspirin (not Tylenol, Advil or Aleve) when you start the hike as a preventative. Take more during the hike.
4. Drink a lot of water during the hike. Do not wait until you are thirsty. You will already be dehydrated. Drink on a schedule. In addition to water, carry powdered Gatorade or another sports drink to add to the water you collect along the trail.
5. Take food that you enjoy eating to help overcome any loss of appetite. Favor carbs over the harder to digest proteins.
Good luck!
