OVERVIEW
Cusco sits at 3,400 meters above sea level. Abra Málaga Pass, where the Inca Jungle route begins, sits at 4,350 meters. These numbers mean something specific to your body: at 3,400 meters the air contains approximately 66 percent of the oxygen available at sea level, and at 4,350 meters that figure drops to around 58 percent. Your cardiovascular system, your respiratory system, and your overall energy levels are all affected by this reduction in available oxygen, and how well you manage the transition from low altitude to high altitude determines a significant part of how you experience the first day and a half of the trek.
The good news is that altitude sickness, in its mild form, is largely manageable with proper preparation and the right decisions in the days before and during the trek. This page tells you everything you need to know.
- WHAT IS ALTITUDE SICKNESS?
Altitude sickness, known medically as Acute Mountain Sickness or AMS, is the body’s response to reduced oxygen availability at high elevation. It is not a sign of weakness or poor fitness. Some of the most physically fit people who have ever stood at the start of the Abra Málaga descent have felt the effects of altitude, and some of the least athletic have sailed through without a moment of discomfort. Individual susceptibility to altitude sickness is determined largely by genetics and previous experience at altitude, not by fitness level.
Mild AMS typically produces headache, fatigue, mild nausea, dizziness, and disrupted sleep. These symptoms usually appear within the first few hours of arriving at altitude and resolve within one to two days as the body acclimatizes. They are uncomfortable but not dangerous in their mild form and do not prevent most travelers from completing the activities planned for Day 1.
Moderate to severe AMS, which can involve more intense headache, vomiting, difficulty walking in a straight line, confusion, or shortness of breath at rest, is a different situation entirely and requires immediate descent to a lower altitude. These symptoms are relatively rare among travelers who have acclimatized properly in Cusco before beginning the trek.
- HOW TO ACCLIMATIZE IN CUSCO
Spend a minimum of two full days in Cusco before your trek departure. Two days is the minimum. Three days is better. The body begins to produce additional red blood cells in response to altitude within 24 to 48 hours of arrival, and the difference in how you feel on Day 3 in Cusco compared to Day 1 is significant and measurable.
During your acclimatization days in Cusco, move slowly. Take the stairs at half speed. Avoid running or any intense exercise. Walk rather than taking taxis for short distances. Your body is working hard enough adjusting to the altitude without adding additional physical stress.
Sleep is where the most important acclimatization work happens. The first night in Cusco is frequently disrupted by the altitude as the body adjusts its breathing patterns to compensate for the reduced oxygen. This is normal. By the second night most travelers sleep significantly better.
Eat light, easily digestible meals during the acclimatization period. Heavy meals tax the digestive system at altitude more than at sea level and can contribute to nausea. Traditional Andean foods including quinoa, potatoes, and soups are well suited to high-altitude digestion.
- HYDRATION
Dehydration accelerates the effects of altitude sickness significantly. The dry air at high altitude, combined with increased respiratory rate as the body tries to compensate for reduced oxygen, means that you are losing water faster than you realize. Drink a minimum of three liters of water per day during your time in Cusco and throughout the trek. This is not a recommendation. It is the single most effective and accessible intervention you can make.
Avoid alcohol during the first two days in Cusco. Alcohol dehydrates the body and suppresses the respiratory drive that altitude acclimatization depends on. The combination of altitude and alcohol consistently produces worse symptoms than either alone.
Coca leaf tea, known locally as mate de coca, is widely available in Cusco and throughout the region. It is a traditional remedy for altitude symptoms that has been used in the Andes for thousands of years and is supported by the experience of the communities that have lived at altitude in this region across generations. Whether or not it produces measurable physiological benefit, it is warming, hydrating, and culturally significant. We recommend it.
- MEDICATION
Acetazolamide, sold under the brand name Diamox, is a prescription medication that accelerates the acclimatization process and reduces the severity of AMS symptoms. It works by increasing the respiratory rate, which helps the body take in more oxygen at altitude. It is widely used by travelers to the Andes and is considered effective and safe when used as directed.
If you are considering acetazolamide, consult your doctor before traveling. It is a prescription medication and requires a medical consultation. It is not appropriate for everyone, particularly those with sulfa drug allergies, and it has side effects including increased urination and tingling in the extremities that are manageable but worth knowing about in advance.
Ibuprofen has been shown in studies to reduce the incidence of headache associated with altitude sickness and is available without prescription. It is a reasonable option for travelers who want to manage headache symptoms without prescription medication.
- THE INCA JUNGLE ROUTE AND ALTITUDE
One of the advantages of the Inca Jungle route compared to the Salkantay Trek or other high-altitude alternatives is that the altitude exposure on Day 1 is brief. You arrive at Abra Málaga Pass at 4,350 meters, spend a short time at that altitude while the bikes are prepared, and then immediately begin descending. By the end of Day 1 you are at 1,500 meters in Santa María, well below the altitude of Cusco. The remainder of the trek stays between 1,400 and 2,430 meters, which are altitudes that the vast majority of travelers handle comfortably after acclimatizing in Cusco.
This means that altitude is a factor primarily for the first two to three hours of the tour. Managing it well in Cusco in the days before departure is the most important preparation you can make.
- SIGNS THAT REQUIRE IMMEDIATE ATTENTION
If you or anyone in your group experiences difficulty walking in a straight line, confusion or unusual behavior, shortness of breath at rest, a persistent cough with pink or frothy mucus, severe headache that does not respond to pain medication, or loss of coordination, inform your guide immediately. These are signs of serious altitude conditions that require immediate descent. Your guide is trained in wilderness first aid and carries emergency oxygen. Do not wait to see if symptoms improve on their own if any of these signs are present.
