Altitude Sickness: Risks, Symptoms, and Prevention

Spending time at high altitudes places significant stress on the human body, particularly without proper acclimatization. Altitude sickness is an umbrella term for medical conditions caused by reduced partial oxygen pressure at elevation. It is a concern not only for mountaineers but also for hikers, soldiers, and professionals working in high-altitude regions.

🔴 Acute Mountain Sickness (AMS)

The most common form of altitude sickness, typically occurring above 2,500 meters (8,200 ft). Susceptibility is highly individual and influenced by ascent rate, physical condition, and previous experience at altitude.

⚠️ Any illness occurring above 2,500 m should be considered altitude-related until proven otherwise.

Symptoms of AMS:

• Headache

• Nausea, vomiting

• Fatigue, weakness, dizziness

• Loss of appetite

• Sleep disturbances

🔴 High-Altitude Cerebral Edema (HACE)

A life-threatening complication of AMS caused by swelling of brain tissue.

Symptoms of HACE:

• Confusion, altered mental status

• Loss of coordination, imbalance

• Difficulty walking (e.g., inability to stand on one leg)

Treatment:

Immediate descent to a lower altitude and urgent medical care. Supplemental oxygen or administration of dexamethasone may be required.

🔴 High-Altitude Pulmonary Edema (HAPE)

A serious complication that can develop even without prior AMS, caused by fluid leakage into the lungs.

Symptoms of HAPE:

• Increasing shortness of breath, even at rest

• Dry cough progressing to frothy or bubbling cough

• Cyanosis (bluish lips and fingers)

• Severe fatigue, inability to exert

Treatment:

Urgent descent, rest, and, ideally, supplemental oxygen or the use of a portable hyperbaric chamber.

What Causes Altitude Sickness?

The primary factor is the reduced partial pressure of oxygen with increasing altitude. The air becomes “thinner,” meaning fewer oxygen molecules per volume, and therefore less oxygen reaches the body. The body compensates with increased heart rate and breathing frequency and eventually produces more red blood cells. Without sufficient acclimatization, however, this adaptation is inadequate.

Preventing Altitude Sickness

• Ascend gradually — no more than 300–500 m per day above 3,000 m
  
• Include a rest day every 2–3 days without further ascent
• Stay well hydrated; avoid alcohol and heavy exertion
• Follow the principle “climb high, sleep low” — ascend during the day, but sleep at a lower altitude

• Preventive use of Acetazolamide (Diamox) after consulting a physician

Treatment

• Mild AMS symptoms:
  Rest, avoid further ascent, or descend slightly; ensure adequate hydration; use pain relievers (ibuprofen, paracetamol).
  
• Severe HACE or HAPE symptoms:
  Immediate descent, oxygen therapy, urgent medical care, and medication as indicated (dexamethasone, nifedipine).
  

Conclusion

Altitude sickness is a risk that can never be entirely excluded. The higher the altitude, the greater the chance of severe complications. The key to safe activity in high mountains is careful prevention, respect for acclimatization limits, and early recognition of warning signs.