Mountain Sickness: Prevention & AMS Protocol

The Himalayas offer extraordinary experiences, but altitude demands respect.

As you climb higher, the amount of oxygen available to your body decreases. Some trekkers may develop Acute Mountain Sickness (AMS) as their body adjusts to the altitude.

AMS can affect anyone, regardless of age, fitness level or previous trekking experience.

At Trip My Soul, we believe that reaching the summit is never more important than your safety.

Acute Mountain Sickness is an altitude-related illness that can develop after ascending to higher elevations before the body has fully acclimatised.

Symptoms commonly include headache, nausea, dizziness, fatigue, loss of appetite, vomiting and difficulty sleeping.

Symptoms commonly begin within several hours after reaching a higher altitude and often become noticeable during or after the first night.

Remember: AMS is not a test of fitness. Even very fit trekkers can experience altitude sickness.

At higher altitude, atmospheric pressure decreases and less oxygen is available with each breath.

Your body needs time to adapt. The most important protection is therefore gradual acclimatisation.

Going too high too quickly increases the risk of altitude illness.

1. Ascend Gradually — avoid unnecessary rapid altitude gain. Once above approximately 3,000 metres, established medical guidance recommends limiting increases in sleeping altitude to around 500 metres per day, with additional acclimatisation time as needed. Trek itineraries should be designed with sensible altitude gain and opportunities for acclimatisation.

2. Don't Push Through Symptoms — this is one of the most important rules on a high-altitude trek. If you develop symptoms of AMS, stop ascending and tell your trek leader. Do not continue climbing simply because the group is moving ahead. Worsening symptoms despite rest or treatment are a reason to descend.

3. Stay Hydrated — But Don't Overhydrate — drink regularly according to thirst and activity. Avoid the idea that drinking excessive amounts of water will prevent AMS. The Wilderness Medical Society specifically does not recommend forced or excessive hydration as an AMS-prevention strategy.

4. Avoid Alcohol — alcohol can interfere with acclimatisation and can worsen sleep-related problems at altitude. The CDC recommends avoiding alcohol during the first 48 hours at high altitude.

5. Pace Yourself — at altitude, your normal walking pace may feel much harder. Follow a comfortable rhythm: slow, steady, consistent. Don't race other trekkers. A slower pace allows you to conserve energy and makes it easier to recognise changes in how you feel.

Mild AMS may include headache plus one or more of: nausea, dizziness, fatigue, poor appetite, difficulty sleeping.

These symptoms should never be ignored. Tell your trek leader immediately.

Early reporting allows the team to monitor you and decide whether you should rest, stop ascending or descend.

Step 1 — Identify: the trek leader or guide checks the trekker's symptoms and recent altitude gain. Other possible causes of similar symptoms — such as dehydration, exhaustion, infection or other medical problems — may also need to be considered.

Step 2 — Stop Ascent: if AMS is suspected, no further ascent until symptoms have resolved. The trekker should rest and remain under observation.

Step 3 — Monitor: the TMS team monitors symptoms, level of alertness, walking ability, breathing, general condition and response to rest/treatment. A pulse oximeter may be used as an additional monitoring tool, but oxygen saturation alone should not be used to diagnose or rule out AMS.

Step 4 — Reassess: if symptoms improve and the trekker is otherwise well, the medical/trek team determines whether continuing is appropriate. If symptoms remain or worsen, do not ascend — descent should be considered, and worsening symptoms despite treatment require descent.

Descent is particularly important when symptoms are worsening, symptoms do not improve at the same altitude, there are signs of severe altitude illness, the trekker develops neurological symptoms, or the trekker develops significant breathing difficulty.

A descent of approximately 300 metres or more can produce rapid improvement in AMS symptoms in many cases.

AMS can progress to much more serious conditions.

HACE — High-Altitude Cerebral Edema: warning signs include confusion, altered behaviour, severe drowsiness, difficulty walking normally, loss of coordination and reduced consciousness.

HAPE — High-Altitude Pulmonary Edema: warning signs include breathlessness at rest, increasing difficulty breathing, persistent cough, marked weakness, chest congestion or tightness, and blue/grey lips or skin.

These are medical emergencies.

If HACE or HAPE is suspected: stop ascending, inform the trek leader immediately, begin descent as soon as practically possible, minimise exertion, use supplemental oxygen if available and appropriate, and arrange urgent medical evacuation / medical care.

For suspected HACE, urgent descent is recommended. For suspected HAPE, descent and oxygen are also central treatments where available.

Never wait for symptoms to become severe before acting.

Acetazolamide is a recognised medication for prevention of AMS and can also be used for treatment in appropriate circumstances. The Wilderness Medical Society and CDC provide specific dosing recommendations.

However, medication should be used only after appropriate medical advice.

Trip My Soul does not recommend that trekkers start prescription medicines on their own simply because they are going on a trek.

Discuss your individual risk, medical history, allergies and medication options with a qualified healthcare professional before the trek.

Portable oxygen canisters marketed for trekking are not a substitute for proper acclimatisation or emergency treatment.

Similarly, "oxygen bars," supplements and forced hydration have not been shown to reliably prevent AMS.

The best protection remains: proper acclimatisation + sensible pacing + early recognition + prompt action.

Every trekker should: understand AMS symptoms, tell the trek team if feeling unwell, avoid alcohol during initial acclimatisation, maintain normal hydration, follow the planned itinerary, avoid unnecessary rapid ascent, carry prescribed medicines, inform TMS about relevant medical requirements, and never hide symptoms to reach the summit.

Rule 1 — Never ascend while experiencing altitude-illness symptoms.

Rule 2 — Never hide symptoms from your trek leader.

Rule 3 — If symptoms worsen, descend.

Rule 4 — Confusion, loss of coordination or severe breathing difficulty is an emergency.

Rule 5 — The summit is optional. Your safety is not.

At Trip My Soul, a successful trek isn't simply about reaching the highest point.

It's about returning safely with memories you'll want to keep forever.

Our trek leaders and guides are responsible for monitoring participants and responding to changing conditions, but every trekker also has a responsibility to speak up when something doesn't feel right.

Don't hide the headache. Don't ignore the nausea. Don't push through worsening symptoms. Speak to your trek leader.

Because in the Himalayas: knowing when to turn around is also a mark of a great trekker.

This guide is for general trekking education and does not replace professional medical advice, diagnosis or treatment.

Altitude illness can become life-threatening. Trekkers with significant medical conditions, previous serious altitude illness, or concerns about their ability to trek at altitude should consult a qualified healthcare professional before undertaking a high-altitude trek.

In an emergency, seek professional medical assistance and evacuation as soon as possible.