Increases in altitude can cause hypertension by putting your body in a state of low oxygen. Treatment for this condition involves acclimatization, oxygen therapy, and medications when necessary.

When the pressure of blood within the walls of your arteries becomes high enough to damage your cardiovascular system, it’s known as hypertension or high blood pressure. High blood pressure can have a variety of causes, and it can be a temporary state or a chronic medical condition.

Climbing a mountain or increasing your distance above sea level in any other way is one situation in which it’s possible to experience a type of temporary hypertension called high altitude hypertension, also known as elevation-induced pulmonary hypertension.

High altitude can cause or worsen hypertension in some people by affecting the body’s gas exchange process and reducing oxygen saturation. It falls under the umbrella of acute mountain sickness (ACS) or altitude sickness, a condition that can cause a variety of low-oxygen symptoms, including high blood pressure.

At sea level, the pressure of oxygen within the alveoli (air sacs) of your lungs is higher than that of your blood, allowing oxygen to diffuse into the bloodstream effectively.

When you ascend to altitudes above 2,500 meters (8,200 feet), atmospheric pressure decreases overall as other gas particles in the air diminish. This lowers the pressure of oxygen in the environment and your alveoli and makes it difficult for oxygen to diffuse into your bloodstream.

Poor oxygen diffusion can lead to hypoxia, or too-low oxygen levels. To compensate, your body kicks off a cascade of reactions, including increasing heart rate, constricting blood vessels in the lungs, and retaining fluid, all of which can elevate blood pressure.

Who should not go to high altitudes?

Not everyone who ascends to high altitudes experiences problematic hypertension, but some people may have an elevated risk.

Discuss any upcoming altitude changes with your doctor if you:

  • live with unmanaged hypertension
  • have previously experienced altitude sickness
  • have a medical history of heart conditions
  • live with a respiratory disease like COPD or asthma that may compound oxygen loss
  • are experiencing pregnancy-related complications
  • have had recent cardiac or respiratory surgery
  • live with conditions affecting your blood vessels, like diabetes
  • are advanced in age

Symptoms of altitude-induced hypertension are similar to those of general hypertension but specific to circumstances where you’ve increased your elevation significantly.

You may notice:

When symptoms are severe, descend to a lower altitude and seek medical attention.

The first management strategy for mild altitude-induced hypertension is to slow your rate of ascent. Your body is capable of adjusting to decreased levels of available oxygen if given enough time (acclimatization), though it can take days or weeks, depending on individual factors like age and overall health.

Current standards for the best rate of altitude ascension suggest staying below 500 meters of ascension a day for climbs over 2,500 meters. At least one day of acclimatization should be taken at the 2,500-meter mark and again for every 1,000 meters of additional ascent.

Additional exercise and alcohol consumption should be avoided during the acclimatization period, and ascent should not be continued if you develop altitude sickness symptoms.

When symptoms are severe, descent to lower altitude and oxygen therapy may be necessary, and a doctor might administer medications that help lower blood pressure, reduce inflammation, and relieve vasoconstriction.

Will everyone experience hypertension at high altitude?

Not everyone will develop hypertension at high altitudes. Fitness level, genetics, rate of ascent, and hydration/nutrition can all matter.

You may be more likely to experience high altitude hypertension if you don’t take time to acclimate, if you’re dehydrated, and if you have pre-existing conditions. Even in the best physical health, the higher you go in elevation, the more likely you are to experience elevated blood pressure.

Altitude hypertension refers to elevated blood pressure due to changes in atmospheric pressure and oxygen saturation. It’s the result of too-low levels of oxygen in your body which raise blood pressure in a variety of ways, including increasing heart rate, causing vasoconstriction, and promoting fluid retention.

If you experience high altitude hypertension, allowing yourself time to acclimate can help, though severe symptoms may require oxygen therapy and descent to more favorable atmospheric pressures.

If you have a history of hypertension or underlying conditions like heart disease, speak with your doctor before significant altitude climbs.