Symptoms of altitude sickness usually develop between 6 and 24 hours after reaching altitudes more than 2,500m above sea level. Symptoms are similar to those of a bad hangover and include: headache.

At what elevation does altitude sickness start?

The condition generally occurs at altitudes higher than 8,000 feet (ft), or 2,500 meters (m), and is usually due to a lack of oxygen. A person who is not used to high altitudes is most at risk of developing altitude sickness. The condition is not to be taken lightly and can lead to serious complications.

Can you get altitude sickness at 5000 feet?

When changes in altitude overpower our ability to acclimatize, we can end up with high altitude illness. This can occur at elevations as low as 4-5,000 feet (the city of Denver, Colorado). More commonly, it develops at an altitude of approximately 8,000 feet or above.