This checklist comes directly from our own days at altitude: the Cotopaxi refuge at 4860m and family days around Sacred Valley and Cusco. These are not generic signs from a brochure; these are the patterns we actually saw in our kids.
Symptoms We Watched For
- Headache that worsens with movement (especially after climbs).
- Nausea and appetite drop, often before obvious exhaustion.
- Child becoming unusually quiet or withdrawn. This was one of our most reliable warning signs.
- Dizziness and faster fatigue on what would normally be easy walking.
- Poor sleep followed by flat energy the next morning.
What Helped in Practice
- Immediate pace reduction and full rest blocks.
- One activity per day max at altitude; multi-stop days were consistently worse for us.
- A backup split plan where one adult can stay with the affected child.
- Hydration (seriously, constant water) and simple meals, not heavy foods.
- No "push through" mindset on bad symptom days. Every time we did less, recovery was faster.
- We didn't use pharmaceutical interventions (like dexamethasone or acetazolamide), but some families do. Consult your doctor before high-altitude trips with kids on medication.
When We Changed Plans
When one of our boys was clearly affected, we paused the full plan rather than trying to keep everyone together at all costs. On one Cotopaxi day this meant one child stayed back while the rest continued. In Peru it meant reducing how much we tried to pack into one day. That flexibility was the biggest practical win of the trip.