Which of the following is NOT an early sign of Acute Mountain Sickness?

• A. Seizures
• B. Headache
• C. Nausea
• D. Sleep disturbance

Answer: (A)

Early signs of Acute Mountain Sickness are mild symptoms that reflect brain hypoxia and typically appear within hours of arriving at high altitude. The most common early signs are a new or worsened headache, along with nausea (and sometimes vomiting) and sleep disturbances such as insomnia or restless sleep. These symptoms signal the body reacting to reduced oxygen and fluid shifts in the brain.

Seizures, on the other hand, do not fit with the typical early presentation. They indicate more severe brain involvement, such as progression toward high-altitude cerebral edema or another neurological issue, which is not considered an early sign of AMS. If seizures occur at altitude, it’s an emergency situation requiring rapid descent, oxygen, and medical evaluation.