High Altitude Cerebral Edema (HACE) is a serious condition that can occur when individuals ascend to high altitudes, typically above 8,000 feet (2,400 meters). It results from the swelling of the brain due to a lack of oxygen, leading to symptoms such as headache, confusion, and difficulty walking. HACE is often a progression from Acute Mountain Sickness (AMS) and requires immediate medical attention. Treatment for HACE involves descending to a lower altitude and administering supplemental oxygen. In severe cases, medications like dexamethasone may be used to reduce brain swelling. Prevention strategies include gradual ascent and proper acclimatization to high altitudes.