If your child is showing signs of altitude sickness, the most important step is to stop ascending and, if symptoms don’t improve within a few hours, descend to a lower elevation. Altitude sickness can affect children at elevations as low as 8,000 feet, and kids are at least as susceptible as adults. The challenge with children, especially young ones, is that they often can’t clearly describe what they’re feeling, so recognizing the signs early falls on you.
Recognizing Symptoms at Different Ages
Older children who can talk about how they feel will typically complain of a headache, which is the hallmark symptom. They may also say they feel nauseous, have no appetite, or can’t sleep. Vomiting, dizziness, and fatigue round out the common picture. These symptoms usually appear within 6 to 12 hours of arriving at a higher elevation.
Babies and toddlers can’t tell you their head hurts. Instead, watch for excessive fussiness or irritability that seems out of proportion to the situation. Other red flags in young children include being less playful than normal, pale skin, refusing to eat, and sleeping significantly more or less than usual. Because these behaviors overlap with so many other childhood issues (teething, missed naps, travel stress), it helps to assume altitude could be the cause if you’ve recently gained elevation.
What to Do When Symptoms Appear
The single most effective treatment for altitude sickness is descent. Even dropping 1,000 to 2,000 feet in elevation often brings noticeable relief. If you’re hiking, stop going up. If you’re at a mountain resort, consider driving to a lower town for the night. Symptoms that are caught early and addressed with descent typically resolve within hours.
While you’re managing the situation, keep your child well hydrated. Fluid needs increase at altitude because dry mountain air and faster breathing pull moisture from the body. Encourage frequent small sips of water or diluted electrolyte drinks. A good rule of thumb: if your child’s urine is dark yellow, they need more fluids. Light or pale yellow means they’re adequately hydrated.
For headache relief, children’s ibuprofen or acetaminophen at the standard dose for your child’s weight can help. Rest in a comfortable position, ideally not lying completely flat if they’re feeling nauseous. Carbohydrate-rich snacks like crackers, bread, or fruit are easier to tolerate than heavy or fatty meals and provide quick energy the body can use efficiently at altitude.
When Altitude Sickness Becomes Dangerous
Mild altitude sickness is uncomfortable but not dangerous. The two serious complications, high-altitude pulmonary edema (fluid in the lungs) and high-altitude cerebral edema (brain swelling), are rare but life-threatening. Recognizing them early is critical because both require immediate descent and emergency medical care.
Signs that your child may be developing fluid in the lungs include shortness of breath even while resting, a persistent dry cough, extreme weakness, and a mild fever. In younger children, this can show up as rapid breathing, refusal to feed, and unusual paleness or a bluish tint around the lips.
Brain swelling is the most dangerous progression. The key warning signs are confusion, extreme sleepiness or lethargy that goes beyond normal tiredness, difficulty walking or unusual clumsiness (called ataxia), and altered mental status. If your child seems “out of it,” can’t walk straight, or is unusually difficult to rouse, treat it as an emergency. Begin descending immediately and call for help. Oxygen, if available, should be started right away.
Medication Options for Children
Acetazolamide is the primary prescription medication used to both prevent and treat altitude sickness in children. It works by changing the acid balance in the blood, which stimulates faster, deeper breathing and helps the body acclimatize more quickly. The CDC recommends a preventive dose of 1.25 mg per kg of body weight every 12 hours (up to 125 mg per dose), and a treatment dose of 2.5 mg per kg every 12 hours (up to 250 mg per dose).
This medication is something to discuss with your child’s pediatrician before your trip, not something to figure out on the mountain. It’s worth noting that acetazolamide helps with mild altitude sickness and aids acclimatization, but it is not recommended for treating moderate to severe cases or cerebral edema, where descent and emergency care are the priorities. Children with diabetes need extra caution, as altitude illness itself can trigger diabetic complications that become harder to manage while on this medication.
Preventing Altitude Sickness Before It Starts
The best strategy is a gradual ascent. If you’re driving from sea level to a ski resort at 9,000 or 10,000 feet, consider spending a night at a mid-elevation town (around 5,000 to 6,000 feet) on the way up. Once above 8,000 feet, try not to increase your sleeping elevation by more than about 1,500 feet per day. Build in a rest day for every 3,000 feet of elevation gain.
On the first day at altitude, keep activity light. Children naturally want to run around and explore, but heavy exertion before the body has adjusted increases the risk of symptoms. Save the big hike or ski day for day two or three. Encourage your child to drink water frequently starting the day before you gain elevation, and prioritize carbohydrate-heavy meals, which the body processes more efficiently than protein or fat in low-oxygen conditions. Research on nutrition at altitude suggests carbohydrates should make up at least 60% of caloric intake during the adjustment period.
If your child has had altitude sickness before, they’re more likely to get it again. In that case, asking your pediatrician about preventive acetazolamide before the trip is reasonable. Children with pre-existing lung conditions, heart problems, or sickle cell disease face higher risks at altitude and need a medical consultation before any high-elevation travel.
Monitoring Your Child at Altitude
A portable pulse oximeter, the small clip-on device that reads blood oxygen levels through the fingertip, can provide useful information. At sea level, a healthy child over age one typically maintains oxygen saturation above 95%. At altitude, readings naturally drop, but sustained levels at or below 90% in children under one, or at or below 93% in older children, suggest meaningful oxygen deprivation. Keep in mind that there aren’t well-established altitude-adjusted targets for children, so use the numbers as one piece of the puzzle alongside how your child looks and acts.
The most reliable monitor, though, is your own observation. Check in frequently. Ask verbal kids how their head feels. Watch younger ones for changes in energy, mood, appetite, and skin color. Altitude sickness tends to worsen overnight, so pay close attention to how your child seems at bedtime and first thing in the morning. If symptoms are getting worse rather than better after a night’s rest at the same elevation, it’s time to go lower.