Altitude Sickness on Friendship Peak — What Nobody Tells You Before You Go

Altitude: 5,289m | Risk starts: 3,000m | Season: May–June, Sep–Oct

The Thing Most Operators Don't Say Before You Book

Altitude sickness turns back more Friendship Peak climbers than bad weather, poor fitness, or wrong gear — combined. We've seen it happen to people who trained hard, planned well, and genuinely wanted to reach the top.

The problem isn't that altitude sickness is unpredictable. The problem is that most people arrive not knowing what to watch for, not knowing what to do when something feels off, and — most dangerously — not knowing the difference between "I feel a bit rough" and "I need to go down right now."

If you haven't already taken the Friendship Peak Fitness Test — Are You Ready? before planning this expedition, that's a good place to start. Physical fitness and altitude readiness are two different things, and both matter.

What's Actually Happening to Your Body Up There

At 5,289 metres, the air has roughly half the oxygen you've been breathing your entire life. Your body isn't built for that — not straight away. It can adapt, but it needs time to do it.

When you climb faster than your body can adjust, things start going wrong. Blood vessels in the brain dilate. Fluid pressure builds. Your head throbs. Your stomach turns. Your legs feel like they belong to someone else.

That's altitude sickness. And on Friendship Peak, the way the route is structured makes it a real concern at multiple stages:

You're gaining over 2,000 metres in two to three days. That's aggressive. Knowing this before you leave changes how seriously you treat every small symptom along the way.

AMS, HAPE, HACE — Three Different Things

Most people have heard of altitude sickness. Very few know there are actually three separate conditions — and they don't work the same way. Knowing which one you're dealing with changes what you do about it.

AMS — The One You're Most Likely to Meet

Acute Mountain Sickness is common above 3,000 metres and usually shows up 6 to 12 hours after reaching a new altitude. Most of the time it's manageable. The problem is when people feel it coming and decide to push through anyway.

Mild AMS feels like:

• A dull headache behind your eyes or across your forehead

• Tiredness that seems out of proportion to what you've actually done

• No appetite — food that sounded fine in Manali now turns your stomach

• Slightly nauseous, maybe dizzy when you stand up fast

• Sleep that keeps breaking — you wake up gasping sometimes

Moderate AMS feels like:

• A headache that paracetamol doesn't touch

• Actual vomiting, not just queasiness

• Walking feels off — your feet aren't going where you expect

• Breathless even when you're just sitting still

One rule that matters more than anything else here — if your symptoms aren't improving after 24 hours at the same altitude, you go down. Not after one more sleep. Not in the morning. Now.

HAPE — When It Gets Into the Lungs

HAPE is fluid building up inside the lungs. It's less common than AMS but it moves fast and it's far more dangerous. This one doesn't give you much warning time.

Watch for:

• A dry cough that starts getting productive — especially if what comes up is pink or frothy

• Breathlessness that doesn't stop even when you rest

• A crackling or gurgling sound when someone breathes

• Lips or fingertips going bluish

If you see any of these, descent starts immediately. Not at first light. Not after the weather clears. Right now. Supplemental oxygen if it's available. A Gamow bag if going down immediately isn't possible. This is a medical emergency — and the window is shorter than most people realise.

HACE — When It Gets Into the Brain

HACE is what happens when AMS gets ignored and pushed through. Fluid accumulates in the brain. It progresses fast and it's the most serious of the three.

Watch for:

• A headache so severe that nothing touches it

• Confusion — saying things that don't make sense, not tracking conversations

• Impossible to keep awake

• Failing the ataxia test (below)

The Ataxia Test — learn this before you go above 4,000m: Ask the person to walk 10 steps in a straight line, heel to toe. If they stagger, veer sideways, or can't do it — treat it as HACE and start descending immediately. This takes 20 seconds. Almost nobody talks about it. Every person on this mountain should know it.

What Actually Prevents Altitude Sickness

Most altitude problems on Friendship Peak aren't bad luck. They come from going too fast, drinking too little, and saying something too late. Here's what genuinely works.

Go up slowly. Above 3,000 metres, your sleeping altitude shouldn't increase more than 300 to 500 metres per day. The acclimatisation walk built into TrekYaari's Day 4 itinerary follows the "climb high, sleep low" principle — it's not filler, it's the most important day on the route.

Drink more than you think you need. At altitude you lose moisture through breathing much faster than at sea level, and your thirst becomes unreliable. Three to four litres a day above 3,000 metres is the minimum. Check your urine colour — dark yellow means drink more right now.

No alcohol. It dilates blood vessels, wrecks sleep, and dehydrates you — three things that independently increase AMS risk. Go easy in Manali too in the days before the climb starts, not just above base camp.

Say something early. Nobody wants to be the person who mentions a headache and slows the group down. But catching AMS early means it resolves fast with rest and water. Catching it late means a helicopter. Tell your leader the moment something feels off — not after dinner, not tomorrow morning.

Get some altitude experience first. If you've never been above 4,000 metres, Friendship Peak is a significant first. A trek like Beas Kund (3,700m) or Hampta Pass (4,270m) beforehand isn't just mental prep — it triggers real physiological changes that make your body genuinely better at handling altitude. The Friendship Peak Fitness Test — Are You Ready? will tell you honestly whether you're physically ready to take that on.

How TrekYaari Handles This on the Mountain

SpO₂ checks twice a day above 3,500m. Every participant's blood oxygen gets checked morning and evening. Below 85% triggers immediate assessment. What matters more than any single reading is the trend — a number dropping across two consecutive checks triggers action even if you feel perfectly fine. Most operators check once a day. The difference matters because altitude problems build slowly before they don't.

Equipment on every expedition. Pulse oximeter, supplemental oxygen, and a Gamow bag — a portable hyperbaric chamber that simulates descent by increasing the air pressure around the person inside it. When it's dark or weather makes going down immediately impossible, a Gamow bag buys critical time.

Descent is never negotiated. If your symptoms aren't resolving, you go down. The expedition leader makes that call — not the group, not you, not any other consideration. There's no conversation to be had once that decision is made.

Diamox — Have This Conversation With Your Doctor First

Diamox (acetazolamide) helps by stimulating faster breathing at altitude, which helps your blood carry more oxygen. Used correctly it works — but it's not right for everyone and it's not something to sort out the night before departure.

• It's a prescription drug in India — you need a doctor's sign-off before you travel

• It contains sulphonamide — sulfa allergy means you cannot take it

• Have this conversation at least 4 weeks before departure so there's time to check tolerance

• It doesn't prevent HAPE or HACE, and it doesn't replace proper acclimatisation

• Common side effects — tingling in fingers and toes, frequent urination

TrekYaari doesn't prescribe or dispense it. If you're already taking it when you arrive, tell your expedition leader on Day 1.

Come Prepared — Not Surprised

Altitude sickness isn't random bad luck. The trekkers who arrive at Manali with prior altitude experience, a trained body, and a real understanding of what to watch for have dramatically better summit outcomes than those who arrive hoping it won't happen to them.

The mountain is the same for everyone. What changes is what you bring to it.

Read our complete Friendship Peak Expedition guide — from acclimatisation protocol to exactly what you'll eat on the mountain.

And if your physical preparation hasn't started, the 8-Week Training Plan for Friendship Peak is where to begin.