Everything You Need to Know About “Soroche”

Altitude doesn’t discriminate: it affects Olympic athletes and sedentary people equally. But it can be prevented and managed.

The Essentials in 60 Seconds

The Truth You Need to Know

Altitude sickness is the most underestimated factor by travelers to the Inca Trail.

Many think: “I’m in good shape, it won’t affect me” or “I’m young, I’ll be fine.” Wrong.

Altitude has no favorites. We’ve seen marathoners suffer while older untrained people passed calmly. Everyone’s body reacts differently, and there’s no way to predict it with certainty.

The good news: With adequate preparation, 95% of people complete the Inca Trail without serious altitude problems.

What is Altitude Sickness?

Altitude sickness—known as “soroche” in Peru, “apunamiento” in Argentina, or AMS (Acute Mountain Sickness) in medical terminology—is the natural reaction of the human body to the lower amount of oxygen available at high altitudes.

The Science Explained Simply

The higher the altitude, the lower the atmospheric pressure. Less pressure means less oxygen in each breath.

At Warmiwañusca Pass (4,215m), you breathe with only 60% of the oxygen your body is used to at sea level. It’s as if out of every 10 breaths, 4 don’t count.

Why Does It Affect Everyone Differently?

Factors that DO NOT predict if you’ll suffer altitude sickness:

• Physical condition (athletes suffer same as sedentary)
• Age (young and old have similar risk)
• Gender (men and women equal)
• Having been at altitude before (you may not have symptoms one trip and yes the next)

Factors that DO influence:

• Speed of ascent (climbing fast = more risk)
• Hydration (dehydration worsens everything)
• Personal history of previous altitude sickness
• Genetics (some bodies adapt better)
• General health state at time of travel

The Acclimatization Process

Your body can adapt to altitude, but it needs time:

What your body does to adapt:

1. Breathing: Increases respiratory rate
2. Heart: Beats faster to move more blood
3. Blood: Produces more red blood cells (takes days/weeks)
4. Kidneys: Adjust blood pH
5. Cells: Become more efficient using oxygen

Time needed:

• Basic acclimatization: 2-3 days
• Moderate acclimatization: 5-7 days
• Complete acclimatization: 2-3 weeks

For the Inca Trail, 2-3 days in Cusco are sufficient for most people.

The Altitudes You’ll Face

Before the Trek: Cusco

Important: When you land in Cusco, you’re already at 3,400 meters. Acclimatization starts from the moment you exit the plane.

During the 4-Day Inca Trail

The critical day is Day 2. You climb from 3,000 m to 4,215 m in a few hours. If you’re going to have serious problems, it will probably be that day.

During the 2-Day Inca Trail

The 2-day Inca Trail has MUCH lower altitude sickness risk because the maximum altitude is only 2,650 m (vs 4,215 m of the 4-day trek).

Symptoms of Altitude Sickness

Mild Symptoms (Normal, Manageable)

75% of people experience at least one of these upon arriving in Cusco or during the trek:

These symptoms are NORMAL. They generally disappear in 1-3 days with adequate acclimatization. They don’t mean you should cancel your trek.

Moderate Symptoms (Require Attention)

If you experience these, inform your guide immediately:

Action: DO NOT continue ascending. Rest. If doesn’t improve in 30-60 minutes, descent is the only definitive treatment.

Severe Symptoms (MEDICAL EMERGENCY)

These are signs of HACE (High Altitude Cerebral Edema) or HAPE (High Altitude Pulmonary Edema). They are emergencies requiring immediate evacuation:

The good news: These severe cases are VERY RARE on the Inca Trail for two reasons:

1. The maximum altitude (4,215m) is not extreme compared to other treks
2. The ascent is gradual (you start at 2,720m, not 4,000m)

In more than 15 years of operation, we have evacuated due to severe altitude sickness less than 0.5% of our travelers.

How to Prevent Altitude Sickness

Prevention is much more effective than treatment. Follow these steps and you’ll significantly minimize risk.

1. Acclimatization: The Main Key

GOLDEN RULE: Arrive in Cusco minimum 2 full days before the trek.

Ideal acclimatization program:

What TO DO During Acclimatization

✅ Walk slowly — Your body is working extra just to function

✅ Drink lots of water — 3-4 liters per day, even if not thirsty

✅ Eat light — Small frequent meals, avoid heavy fats

✅ Sleep enough — Rest helps adaptation

✅ Drink coca tea — Traditional Andean remedy, available at all hotels

✅ Avoid effort — Not the time to climb mountains or take exhausting tours

✅ Listen to your body — If you feel bad, rest more

What NOT TO DO During Acclimatization

❌ Arrive and start trek the next day — Most common mistake #1

❌ Drink alcohol — Dehydrates and worsens all symptoms

❌ Smoke — Further reduces available oxygen

❌ Take exhausting tours the first days — Rainbow Mountain, etc.

❌ Eat excessively — Digestion consumes oxygen

❌ Ignore symptoms — “It’ll pass” can be dangerous

❌ Take sleeping pills — Can mask symptoms and affect breathing

2. Constant Hydration

Altitude increases fluid loss through:

• Faster breathing (you lose water vapor)
• Drier air at altitude
• Increased urine production (body adjusts pH)

Recommendation: 3-4 liters of water per day throughout the trek

Signs of good hydration:

• Clear and frequent urine (every 2-3 hours)
• Lips not cracked
• No extreme thirst

Tip: Always carry water in your day backpack. We refill at each campsite.

3. Smart Eating

4. Walking Pace

“Pole pole” — Slowly, slowly.

At altitude, walking fast doesn’t get you to the end of the day faster. It only makes you suffer more and increases altitude sickness risk.

Practical rule: If you can’t talk while walking, you’re going too fast.

Our guides are trained to set an appropriate pace. Trust them even if you feel you’re going “too slow”.

5. Preventive Medications

Acetazolamide (Diamox)

Should I Take Diamox?

It’s a personal decision in consultation with your doctor. Many people complete the Inca Trail without medications, only with good acclimatization.

Consider Diamox if:

• You have history of altitude sickness on previous trips
• You have little time to acclimatize (less than 2 days)
• You want to maximize your prevention
• Your doctor recommends it

You don’t need Diamox if:

• You have adequate time to acclimatize
• You’ve never had altitude problems
• You prefer natural acclimatization
• You have contraindications (sulfa allergy, kidney problems)

6. Natural Andean Remedies

The inhabitants of the Andes have lived at high altitude for thousands of years. Their traditional remedies work:

Coca Tea (Mate de Coca)

Recommendation: Drink 2-3 cups of coca tea per day during your stay in Cusco and during the trek.

Chewed Coca Leaves

Coca Candies

Muña (Andean Mint)

Managing Altitude Sickness During the Inca Trail

Day 1: Initial Monitoring

Altitude: 2,720 m → 3,000 m Risk: Low

What to expect:

• If you acclimatized well in Cusco, you should feel fine
• Possible greater fatigue than normal (you’re walking at altitude)
• Body still adapting

What to do:

• Calm pace, no rush
• Drink water constantly
• Inform guide if you feel unusual symptoms
• Save energy for day 2

Day 2: The Critical Day

Altitude: 3,000 m → 4,215 m → 3,600 m Risk: HIGH

This is the day where most problems occur. You climb 1,200 meters in a few hours to Warmiwañusca Pass.

What to expect:

• Significant shortness of breath on the climb
• Possible mild headache
• Intense fatigue
• Elevated heart rate
• Possible nausea

What to do:

• VERY slow pace — No hurry, camp waits
• Deep and conscious breathing
• Drink water every 15-20 minutes
• Eat small snacks to maintain energy
• Frequent stops (our guides make them)
• Communicate any concerning symptoms immediately

Warning signs at the Pass:

• Headache that worsens despite painkillers
• Nausea that doesn’t stop
• Confusion or disorientation
• Difficulty walking in straight line

If this occurs: Inform guide IMMEDIATELY. We have portable oxygen and management protocol.

Day 3 and 4: Descent and Recovery

Altitude: Descending toward 2,430 m Risk: Low (you’re descending)

What to expect:

• Significant symptom improvement
• More energy
• Better appetite
• Better sleep

If symptoms WORSEN when descending, something else is wrong. Inform guide.

What We Carry

All our treks include altitude medical equipment:

Oxygen saturation (SpO2):

• Normal at sea level: 95-100%
• Normal in Cusco (3,400m): 88-92%
• Normal at Warmiwañusca (4,215m): 80-88%
• Concerning: Less than 75%
• Dangerous: Less than 70%

Treatment if You Have Symptoms

For Mild Symptoms

For Moderate Symptoms

Critical rule: If moderate symptoms don’t improve in 30-60 minutes of rest, DESCENDING is the only effective treatment.

For Severe Symptoms

MEDICAL EMERGENCY — THERE IS NO TREATMENT IN THE FIELD

1. Administer oxygen
2. DO NOT ascend under any circumstance
3. Immediate descent (even at night)
4. Medical evacuation
5. Activate satellite phone for coordination

The only cure for severe altitude sickness is to descend. No medication substitutes descent.

Myths and Truths About Altitude Sickness

MYTH: “I’m in good physical shape, it won’t affect me”

TRUTH: Physical condition DOES NOT protect against altitude sickness. Your heart and muscles can be perfect, but your cells still need time to adapt to less oxygen. We’ve seen marathoners suffer more than older untrained people.

MYTH: “I’m young, young people don’t suffer soroche”

TRUTH: Age is NOT a determining factor. In fact, young people sometimes suffer more because they tend to:

• Overexert themselves
• Ignore symptoms
• Not take acclimatization seriously
• Compete with others in the group

MYTH: “I took Diamox, I’m 100% protected”

TRUTH: Diamox helps but DOES NOT guarantee immunity. It’s one more tool, not a magic solution. Even with Diamox you must:

• Acclimatize adequately
• Hydrate well
• Go at slow pace
• Listen to your body

MYTH: “Coca tea is a drug”

TRUTH: The coca leaf in its natural form (tea, chewed, candies) DOES NOT have narcotic effect. The concentration of alkaloids is minimal. It’s used by millions of Andeans daily for thousands of years. It’s completely legal in Peru, Bolivia and parts of Argentina.

Note: Coca leaf is the raw material for cocaine, but requires intensive chemical processing. Chewing coca is as much a “drug” as eating poppy seeds is consuming opium.

MYTH: “If I didn’t have altitude sickness before, I won’t have it now”

TRUTH: Your altitude response can vary between trips. Factors that change:

• Your current health state
• Hydration level
• Prior sleep quality
• Stress
• Ascent speed

That you didn’t have symptoms on a previous trip DOES NOT guarantee you won’t have them now.

MYTH: “I should drink alcohol to warm up at night”

TRUTH: Alcohol is ENEMY of altitude:

• Dehydrates (opposite of what you need)
• Interferes with acclimatization
• Can mask dangerous symptoms
• Affects sleep quality
• The “warmth” you feel is illusory (vasodilation)

Rule: Zero alcohol until you finish the trek.

MYTH: “If I feel bad, I should continue to not delay the group”

TRUTH: Your health is MORE important than the itinerary. Our guides are trained to handle these situations. We will never pressure you to continue if you’re not well. We have protocols so you can rest or descend if necessary without dramatically affecting the group.

TRUTH: “Climbing slowly helps prevent altitude sickness”

CORRECT. Ascent speed is one of the most important factors. That’s why the Inca Trail, which climbs gradually over 2 days before reaching the maximum point, has lower incidence of severe altitude sickness than routes where you climb quickly.

TRUTH: “Hydration helps significantly”

CORRECT. Dehydration worsens all altitude sickness symptoms. Maintaining optimal hydration doesn’t prevent altitude sickness, but it does reduce its severity.

TRUTH: “Descending is the most effective treatment”

CORRECT. No medication, oxygen or natural remedy is as effective as descending. If you have moderate to severe altitude sickness and descend 500-1000 meters, symptoms improve dramatically in hours.

Frequently Asked Questions

How many days do I need to acclimatize in Cusco?

Minimum 2 full days. Ideal 3 days. More time is unnecessary for Inca Trail altitudes.

Example itinerary:

• Day 1: Arrive in Cusco, rest
• Day 2: Gentle city tour
• Day 3: Sacred Valley or free day
• Day 4: Start Inca Trail

Does the 2-day Inca Trail have fewer altitude problems?

Yes, significantly fewer. The 2-day Inca Trail has maximum altitude of 2,700m (vs 4,215m of 4-day trek). Risk of moderate or severe altitude sickness is minimal on the 2-day version.

Must I take Diamox obligatorily?

It’s not mandatory. It’s a personal decision in consultation with your doctor. Many people (most) complete the Inca Trail without medications, only with adequate acclimatization.

Can I take Diamox if I have sulfa allergy?

1. Diamox (acetazolamide) is a sulfonamide. If you’re allergic to sulfas, it’s contraindicated. Consult alternatives with your doctor.

Does coca tea show up on drug tests?

Technically it can give a mild false positive on some very sensitive tests for a few days after consumption. If you have an upcoming work drug test, consider avoiding it or inform that you were in Peru.

What happens if I have to abandon the trek due to altitude sickness?

We have evacuation protocol. We’ll accompany you to a safe point and coordinate your return to Cusco. Your health is the absolute priority.

Can children have altitude sickness?

Yes, and sometimes they don’t know how to express symptoms. With children you must be extra careful:

• Longer acclimatization
• Observe behavior (irritability, not wanting to eat)
• Very slow pace
• Constant hydration

Is it safe to do the Inca Trail if I have asthma?

Depends on severity. Mild to moderate asthma well controlled is generally not a problem. You should:

• Consult with your doctor beforehand
• Bring your inhalers (rescue and maintenance)
• Inform us of your condition
• Have action plan if there’s crisis

Severe or uncontrolled asthma is a relative contraindication.

Does altitude affect people with high blood pressure?

Altitude can slightly increase blood pressure. If you have hypertension:

• Consult with your doctor beforehand
• Make sure it’s well controlled
• Bring your medication
• Monitor your pressure if possible
• Inform us of your condition

Well-controlled hypertension is generally not a problem.

Can I do the Inca Trail if I’m pregnant?

We don’t recommend the Inca Trail during pregnancy, especially the 4-day trek that reaches 4,215m. Risks include:

• Less oxygen for fetus
• Dehydration
• Extreme physical effort
• Distance from medical care

If you’re in very early first trimester, consult with your obstetrician before deciding.

Don’t Let Altitude Stop You

Altitude sickness is real, but it’s manageable with adequate preparation.

Thousands of people from around the world complete the Inca Trail every year without significant problems. The key is:

1. Acclimatize — Minimum 2 days in Cusco
2. Hydrate — 3-4 liters of water per day
3. Go slow — “Pole pole”, no rush
4. Listen to your body — Communicate symptoms to guide
5. Trust the process — Your body adapts

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