Altitude Sickness Nearly Ruined My Trip – Here’s What Saved Me

Before flying into Cusco, I didn’t think much about altitude sickness. I had read about it, sure. But I assumed staying hydrated and taking it slow would be enough. I was wrong.

By my second day exploring the historic streets of Cusco elevated at about 11,000 feet I felt lightheaded, nauseous, and incredibly sluggish. It felt like my brain and body were moving in different time zones. That experience changed how I plan every high-altitude trip.

Here’s a guide based on what actually worked for me, what the experts recommend, and a few things I wish I had done differently.

What Altitude Sickness Really Feels Like

Altitude sickness (technically called Acute Mountain Sickness or AMS) can feel like a hangover combined with the flu: headaches, nausea, fatigue, dizziness, and sometimes trouble sleeping. Most symptoms kick in after ascending above 8,000 feet (2,500 meters), especially if you ascend too fast.

There are more serious forms too:

• HAPE (High-Altitude Pulmonary Edema): fluid in the lungs
• HACE (High-Altitude Cerebral Edema): brain swelling

These are rare but life-threatening and require immediate descent and medical attention.

How I Prepared Before the Trip

1. I Spent Time at Mid-Altitude First

If you can, plan your itinerary so you spend at least one or two nights at a mid-elevation destination before heading higher. I chose to fly into Arequipa, Peru (which sits at around 7,600 ft or 2,300 meters), and stayed there for two nights. This allowed my body to begin adjusting to thinner air gradually, and by the time I reached Cusco (11,000 ft), the change didn’t feel as shocking. This step alone likely reduced my chances of experiencing severe symptoms. If your route doesn’t include a stopover city, consider spending extra time in a nearby lower-altitude area before moving up.

2. I Started Hydrating Early

Two days before my flight, I consciously increased my water intake aiming for 3–4 liters a day. I also reduced coffee and alcohol, both of which can be dehydrating. Proper hydration helps support circulation and oxygen delivery, both of which become more critical at altitude. I brought a reusable bottle with me, added electrolyte tablets to my water once a day, and monitored how often I was urinating (a good indicator of hydration levels). This simple step made a noticeable difference in how my body responded.

3. I Packed Medications Just in Case

After researching and speaking with my doctor, I brought acetazolamide (Diamox) a commonly prescribed medication that helps your body adjust to altitude by encouraging deeper, faster breathing. I started taking it 24 hours before reaching Cusco and continued for 48 hours after arrival. Some people experience side effects (like tingling fingers or increased urination), but for me, it was mild and worth it. I also packed ibuprofen in case I developed headaches, and rehydration salts to use if nausea or fatigue kicked in. Having these on hand gave me peace of mind and options if symptoms worsened.

What Actually Helped Once I Got There

1. Going Slow

This can’t be overstated. I had originally planned to visit Machu Picchu on day two but that would’ve been a major mistake. Instead, I gave myself time to settle in. I spent the first day relaxing at my hotel, sipping coca tea, and taking short, flat walks around the historic center of Cusco. I sat at outdoor cafes, people-watched, and journaled. Doing as little as possible allowed my body to focus on acclimatizing. If you’re arriving at a similar elevation, I recommend giving yourself at least 24–48 hours of minimal exertion, no matter how tempting it is to jump into sightseeing.

2. Drinking Coca Tea

Coca tea, or “mate de coca,” is a traditional herbal infusion made from coca leaves, widely served throughout the Andes. While scientific evidence on its effectiveness for altitude sickness is mixed, it’s part of the local culture and has been used for centuries to alleviate symptoms. I found it genuinely soothing. It reduced my headache and gave me a gentle boost of energy when I felt foggy. I drank 2–3 cups a day during my first few days. If you try it, note that it’s not advisable to pack coca leaves for flights back home, especially into the U.S. or Europe they’re considered a controlled substance.

3. Eating Light & Carb-Heavy

Heavy meals take more energy to digest and at altitude, your body is already working overtime. I stuck to simple, carb-rich meals like chicken soup, quinoa, bread, potatoes, and rice. I avoided red meat, dairy-heavy dishes, and anything too spicy or greasy. Carbohydrates are easier to process and require less oxygen to metabolize than protein or fat. I also ate more frequently than usual small meals and snacks throughout the day to keep my energy stable. In hindsight, eating this way gave my body the fuel it needed without taxing my system.

4. Using Essential Oils

A small tip that made a surprising difference: peppermint essential oil. I brought a roller bottle with me and applied it under my nose or on my temples whenever I felt queasy. The cooling sensation and strong scent helped curb nausea and made me feel more grounded when I was lightheaded. While not a medical treatment, it’s a gentle, natural option that provided comfort when I needed it most. I now pack it for every high-altitude trip.

Tips I Wish I Knew Earlier

1. Avoid Overexertion

Even simple tasks like walking uphill or climbing stairs can feel surprisingly strenuous at altitude. On my first day in Cusco, I made the mistake of trying to explore too much too soon and I paid for it with pounding headaches and heavy fatigue. Your body needs time to adjust to thinner air and reduced oxygen levels. What I should’ve done: avoid long walks, minimize climbs, and spend the day lounging, reading, or sitting in the sun with a tea. Even brief overexertion can trigger symptoms, so treat your arrival day like a recovery day.

2. Don’t Skip Rest Days

Rest days are critical not optional. Most high-altitude travel experts recommend building in a rest day for every 3,000 ft (1,000 m) you ascend, especially above 8,000 ft. I underestimated this and tried to keep my itinerary packed, which left little room for my body to catch up. On rest days, avoid changing altitude, minimize activity, and give your body a full 24 hours to acclimatize. Trust me, skipping this can lead to prolonged or worsened symptoms later in your trip.

3. Know the Warning Signs

Mild altitude sickness can be annoying but severe symptoms can be dangerous. If you notice intense headaches that don’t go away with rest, nausea that prevents eating or drinking, confusion, persistent coughing, or trouble walking steadily, those are red flags. I met a fellow traveler who brushed off their symptoms and ended up needing oxygen at a clinic. Don’t wait it out. Descend immediately and seek medical help if anything feels off. Your body will tell you what it needs listen to it.

My Go-To High Altitude Packing List

• Acetazolamide (Diamox)
• Ibuprofen or acetaminophen
• Rehydration salts
• Reusable water bottle
• Electrolyte tablets
• Peppermint essential oil
• Lightweight snacks (crackers, granola bars)
• Layers (temperatures can drop fast)

Expert-Backed Prevention Tips

Several top medical sources such as the CDC, Cleveland Clinic, and adventure medicine researchers recommend the following strategies to prevent altitude sickness:

• Ascend gradually: Gain no more than 1,600 ft (500 m) per day above 9,800 ft (3,000 m). Build in rest days every 3,000 ft (1,000 m) gained.
• Consider pre-acclimatization: Use simulated altitude tents or spend time at moderate altitude (~6,000–7,000 ft) for a few nights before ascending higher.
• Stay well hydrated, but avoid overhydration which can also cause electrolyte imbalance. Add electrolytes to your water.
• Eat a high-carb diet (70%+ of calories) during your acclimatization period. Carbohydrates require less oxygen to metabolize than fats or proteins.
• Continue caffeine if you’re a regular coffee or tea drinker to avoid withdrawal, but skip alcohol and sleeping pills in the first 48 hours.
• Use medications like acetazolamide for prevention, and ibuprofen for altitude headaches. In high-risk cases, doctors may prescribe dexamethasone or nifedipine.
• Carry emergency tools: In very high-altitude treks, Gamow bags (portable hyperbaric chambers) and oxygen can save lives.

These are best used under the guidance of a travel doctor or high-altitude specialist.

Final Thoughts

Altitude sickness doesn’t care how fit you are or how many hikes you’ve done. But with the right prep, mindset, and pacing, it doesn’t have to ruin your trip.

If you’re heading to a high-elevation destination soon, I hope this helps you feel more prepared. And if you’ve already been through it, I’d love to hear what worked for you!

FAQs About Altitude Sickness