Altitude Sickness in the Andes: What You Need to Know (and How to Avoid It)

You’re excited about visiting the Anden, but it’s normal to wonder, “Will I get altitude sickness?”

The short, reassuring answer is that for most travelers, it’s manageable.

With a simple plan (acclimatize, hydrate, go at your own pace), most people enjoy the mountains without serious problems.

To help you, we provide clear information, step-by-step prevention measures, and a ready-to-use action plan if symptoms appear.

1) What causes altitude sickness? A simple explanation

As you gain altitude, atmospheric pressure decreases and each breath contains less oxygen.

The body needs time to adapt (breathe a little faster, produce more red blood cells).

Think of it as the air becoming “thinner”: the body has to catch up.

This mismatch between the immediate demand for oxygen und the supply is the main cause of acute altitude sickness.

2) Symptoms: what you are likely to feel and when

Level 1: common and mild symptoms (most frequent)

These usually begin between 6 and 24 hours after ascending and are the most common:

• Headache (mild to moderate)
• Nausea or loss of appetite
• Excessive tiredness or dizziness
• Difficulty sleeping
• Most mild cases improve within 24-72 hours with rest, hydration, and avoiding exertion.

Level 2: Rare but serious symptoms (act immediately)

In very rare cases, mild altitude sickness progresses to high altitude pulmonary edema (HAPE) or high altitude cerebral edema (HACE). Warning signs include:

• Severe breathing difficulty at rest, persistent cough (which may produce foamy or pink sputum): HAPE.
• Confusion, disorientation, severe imbalance, drowsiness, or difficulty speaking: HACE.

If you notice these signs, descend immediately and seek urgent medical attention. Evacuation and oxygen can save your life.

3) The best prevention strategy: a practical, step-by-step plan

Step A: Rule No. 1: Acclimatize (go slowly)

• Use Quito (≈2850 m / 9350 ft) as your acclimatization base before ascending to higher altitudes.
• For trips above 3000 m, follow the general guideline: do not increase your sleeping altitude by more than 300-500 m per day and include a rest day every 3-4 days. This is a WMS recommendation widely used by guides and doctors.

Step B: Hydrate and eat smart

• Drink regularly (aim for 2–3 liters per day, depending on activity and climate).
• Avoid excessive consumption of alcohol and limit caffeine during the first 48 hours.
• During the initial acclimatization phase, favor carbohydrate-rich meals to meet energy needs.

Step C: moderate your activity

• On arrival days, “walk, don’t run”: light walks, stops to take photos, leisurely explorations.
• Leave long walks or strenuous activities until after 24-72 hours of acclimatization.

Step D: useful local remedies (optional)

• Local remedies, such as coca tea, are common in the local culture and may relieve symptoms in some travelers, but they are not a substitute for proven strategies (acclimatization, descent). Consult your doctor if you plan to use them.

Step E: Medication (only on medical advice)

• Acetazolamide (Diamox) is commonly used to help prevent altitude sickness. A widely used preventive regimen is 125 mg twice daily, starting 24-48 hours before ascent and continuing for the first 48-72 hours at altitude; other regimens used by physicians may be higher; always consult your physician. For treatment doses, different protocols exist and a physician’s guidance is required.

4) What to do if symptoms appear: a clear action plan

1. Stop climbing and rest immediately.
2. Hydrate and eat light carbohydrates.
3. If symptoms are mild, wait and monitor them: most mild cases of AMS improve within 24 to 72 hours.
4. If symptoms worsen or signs of HAPE/HACE appear, descend immediately, as descent is the most effective treatment. Arrange for emergency evacuation and oxygen. Do not delay.

5) Quick reference: altitudes and notable peaks (Ecuador)

• Quito: ≈ 2,850 m / 9,350 ft (ideal short-term acclimatization base).
• Cotopaxi: 5,897 m / 19,347 ft (technical glacier climbs; requires guide and acclimatization).
• Chimborazo: 6,263 m / 20,549 ft (Ecuador’s highest peak; serious mountaineering).
  

6) How a local operator (an excellent option) reduces risk, step by step

Booking with a qualified local operator is not mandatory, but it is one of the smartest ways to reduce risk and improve comfort, especially if you are traveling at high altitude for the first time. Here is how a high-quality agency (such as Responsible Travel SA) can help you, naturally and practically:

1. Itinerary design with acclimatization included: Nights in Quito or stops in the valley are scheduled according to accepted acclimatization guidelines (no major changes in sleeping altitude).
2. Trusted local guides: Guides trained to recognize AMS, HAPE, and HACE early on, with clear monitoring and response protocols.
3. Emergency preparedness: guides carry oxygen, first aid kits, and have pre-established contacts for evacuations and clinics, reducing response time if something goes wrong.
4. Cultural and logistical value: they seek out accommodations suitable for acclimatization, advise on safe food and hydration, and reduce stress so you can rest properly.

Responsible Travel SA is one of the best local options due to its local relationships, but it is not the only option. If you prefer to travel independently, follow the same steps above and identify local medical contacts and transportation options before you leave.

7) Quick checklist: what to do before traveling

• Consult your doctor if you have heart or lung disease.
• Consider consulting a doctor about acetazolamide if you plan to make rapid ascents or attempt to reach high peaks.
• Plan for 1-2 days of acclimatization in Quito.
• Bring warm clothing, sunscreen, a reusable water bottle, and any prescription medications.

Book with a tour operator who knows local emergency contacts and carries oxygen (if that makes you feel comfortable).

Your Top Questions  (short and practical)

Altitude sickness is something to be aware of, but it doesn’t have to be an obstacle.

With a sensible pace, hydration, a little planning, and (optionally) the support of a local expert, you’ll spend most of your trip enjoying the scenery, without worrying about symptoms.