SATURDAY, Oct. 4 (HealthDayNews) -- Depending on what kind of asthma you have, your condition can worsen or improve at higher altitudes.

According to Britain's National Asthma Campaign, there is about half the oxygen at heights of 18,000 feet than there is at sea level. Problems don't usually occur until about 8,000 feet, though, and only occasionally as low as 5,000 feet.

Less oxygen means your body has to find ways to adapt. In the first several days at high altitude, you'll increase your breathing rate and volume to take in more oxygen. Over the course of several weeks, your body starts producing more red blood cells, which transport oxygen to the cells, so the cells stay properly oxygenated.

Once you're acclimatized to the new altitude, the asthma shouldn't pose a problem, the National Asthma Campaign says.

On the other hand, people whose asthma is triggered by dust mites could experience dramatic improvement at higher altitudes. That's because the house dust mite can't survive above the snow line.

Heed this advice for problem-free traveling, even at high altitudes:

• If you're planning a trip that will involve visiting high altitudes, talk to your doctor several weeks before leaving so you can agree on a management plan, the National Asthma Campaign advises.
• Be aware that higher altitudes tend to have colder temperatures, which can exacerbate asthma in some people. Climbing may also trigger exercise-induced asthma.
• If possible, ascend slowly over the course of several days so your body has time to adapt.
• Make sure to carry your medication and inhaler with you at all times.
• Warm pressurized inhalers with your hands before using. They may not work properly in freezing conditions.

More information

The American Academy of Allergy, Asthma and Immunology has more on asthma.