Final answer:
Acute mountain sickness (AMS) can occur immediately after reaching an altitude greater than 2000 meters. Symptoms include nausea, vomiting, fatigue, lightheadedness, and nosebleeds. The only treatment is descending to a lower altitude.
Step-by-step explanation:
Acute mountain sickness (AMS), also known as altitude sickness, can occur immediately after reaching an altitude greater than 2000 meters. It is a condition that results from acute exposure to high altitudes due to a low partial pressure of oxygen. Symptoms of AMS include nausea, vomiting, fatigue, lightheadedness, and nosebleeds. The only treatment for AMS is descending to a lower altitude, but pharmacologic treatments and supplemental oxygen can help improve symptoms. AMS can be prevented by slowly ascending to the desired altitude and staying hydrated.