Subacute mountain sickness

Medium urgency
-Moderately severe

It is called Subacute Mountain Sickness when people who do not usually live at high altitudes present symptoms that appear as a result of prolonging their stay for weeks or months above 3,000 m. It is caused by the lack of oxygen that tissues suffer at high altitudes, which causes vasoconstriction of pulmonary arterioles and an increase in red blood cells.

It is caused by the lack of oxygen that tissues suffer at high altitudes, which causes vasoconstriction of pulmonary arterioles and an increase in red blood cells. It triggers pulmonary artery hypertension and overload of the heart's right ventricle.

It manifests with dyspnea, cough, swelling of the face and lower limbs, enlarged neck veins, enlarged liver, ascites, and exertional angina pectoris.

It is diagnosed by clinical history and physical examination.

Treatment is based on abandoning altitude, supportive measures and symptomatic treatment. 

Bibliographic references
  1. Scott A Gallagher. High altitude illness: Physiology, risk factors, and general prevention. UpToDate. Abril 2015
  2. Hackett PH. High-altitude medicine. In: Wilderness Medicine, 6th, Auerbach PS (Eds), Elsevier, Philadelphia 2012. p.2.
  3. Scoggin CH. High-altitude pulmonary edema in the children and young adults of Leadville, Colorado. N Engl J Med 1977; 297:1269.
  4. West JB, American College of Physicians, American Physiological Society. The physiologic basis of high-altitude diseases. Ann Intern Med 2004; 141:789.
  5. Buddha Basnya. Enfermedad de las altitudes. Harrison. Principios de Medicina Interna, 19e. Capítulo 476E
Author
Dr. Patricia Sánchez
Copyright
© TeckelMedical 2026

Symptoms

    Shortness of breath on exertion


    Diastolic blood pressure greater than or equal to 110 mmHg


    Cough


    Short of breath


    Swelling around the eyes

Pre-hospital care recommendations

Descend below a safe altitude (< 8202 feet).
Maintain a fluid intake of 6 - 8 cups per day.