If you’re headed up, here’s how to prepare and treat symptoms, and what to look out for to ensure you stay happy and healthy while closer to the sky. “You’re still breathing 21 percent oxygen, it’s just more spread out,” explains Graham Prather, education manager at National Outdoors Leadership School (NOLS) and in charge of wilderness medicine courses. Essentially, the higher you go, the less efficient your breathing becomes, resulting in less and less oxygen every time you inhale. In response, your body tries to get the oxygen it needs, so you start breathing more rapidly. But despite this effort, there’s still less oxygen making it into your blood and muscles, which is why physical activities feel so much harder at higher elevations. This condition is called hypoxia, and it’s what causes altitude sickness symptoms to set in. “It felt like a really bad hangover,” says Prather about the first time he experienced altitude sickness. It’s a feeling that usually hits within a day or two of arriving at a high-altitude destination, but you may still feel mild symptoms like lightheadedness before that, especially when bending over and standing up quickly, or walking up stairs. Most of the time, these symptoms are not life-threatening and only require acclimatization to abate. But especially at elevations over 10,000 feet, symptoms can worsen and lead to more severe health conditions: High altitude cerebral edema (HACE) or high altitude pulmonary edema (HAPE). “We cannot hydrate away altitude sickness, but we can at least not be dehydrated on top of it,” Prather offers. HACE typically comes with a loss of balance, episodes of confusion, and possibly a severe headache. On the other hand, HAPE presents itself with decreased stamina, breathlessness (even at rest), and a persistent cough that starts out sounding dry and transitions to wet, signaling the presence of fluid in the lungs. HAPE is more common than HACE, but both can be deadly, which is why it’s important to head down in elevation as soon as you start experiencing symptoms. Not even athletes or people in excellent shape are immune. In fact, Prather says those tend to be who he’s most worried about when leading trips, as non-athletes tend to listen to their bodies and pay attention to symptoms, whereas athletes may try to push through the pain or discomfort. Start by planning ahead and allowing enough time for acclimatization. Don’t expect to land in Quito, Ecuador (9,350 feet above sea level), the Himalayas (29,032 feet), or even Denver (5,279 feet) and immediately set out to summit even a moderate peak. Your body needs between 24 and 48 hours to adjust to new altitudes, but the time it takes you to fully acclimatize may vary. The National Outdoor Leadership School’s curriculum specifies that “if you travel to 10,000 feet or above quickly, take two to three rest days with light exercise.” If you take time to get acclimated, symptoms won’t likely hit as hard. Once you’ve given your body time to get used to the new conditions, don’t rush into summiting anything—the faster you climb, the more likely you are to suffer symptoms. If you have a multi-day hike to higher elevations ahead of you, Prather recommends spreading the trip across several more days, so that once you’re above 10,000 feet, you and your team can ascend in stages where each night you sleep at altitudes no more than 1,500 feet higher than the night before. Throw in frequent rest days, too. If you can, consider spending the night at lower elevations, as sleeping at high altitudes is even harder on your body. To do this, you can go on climbing trips during the day, and then go down to your base camp at night. Over-the-counter pain meds like ibuprofen and acetaminophen can help lessen the severity of headaches, but avoid anything stronger, like opiates, which have a similar effect to alcohol and sedatives, Prather says. “You want your respiratory drive to be responsive to the atmosphere you’re in,” he says. If you are expecting to experience altitude sickness, ask your doctor about acetazolamide. This drug can alleviate symptoms of altitude sickness by speeding up your respiratory drive. It works by changing your blood’s Ph to be more acidic, which makes your body believe there’s too much carbon dioxide. As a result, your system makes your breathing faster and deeper in an attempt to eliminate carbon dioxide, resulting in a higher concentration of oxygen. Finally, if altitude sickness persists or worsens despite your best prevention and treatment efforts, take Prather’s words as your new motto: “Don’t go up until your symptoms go down”. If there’s no improvement, it may be time to head to a lower elevation. Don’t worry—you can always try again next time.
