Asthma at high altitude: what every traveller should know

Travelling to high-altitude destinations, like summiting Kilimanjaro or exploring the Himalayas, can be an exciting adventure. But for those with asthma, the thought of thinner air and reduced oxygen can trigger a wave of worry. Does an inhaler help at high altitude? How can you manage symptoms when the air gets thinner and colder? Is there a risk of developing severe conditions like high-altitude pulmonary edema (HAPE)? These are all valid concerns, and preparing for altitude changes is a given for anyone battling asthma.  We will cover everything you need to know about managing your asthma at high altitudes. Knowing how altitude impacts your lungs is crucial for proper medication use and monitoring your symptoms. Whether you are planning a high-altitude trek or a relaxed mountain getaway, keep reading to ensure your holiday is safe and enjoyable.

A man hiking in the snow

At high altitudes, breathing can be difficult, not just for people with asthma, but for everyone. High altitude is generally considered any elevation above 5,000 feet, where the oxygen percentage remains the same at 21%, but the atmospheric pressure drops, making it harder for your body to breathe. Travellers should note that the altitude does not trigger asthma symptoms, but the change in temperature and humidity is the main instigator. Our lungs perform best in warm, humid air, while cold, dry air can irritate them, potentially triggering symptoms. As you ascend, the air gets colder and drier, but not everyone with asthma will experience issues; some may find the cleaner air refreshing for their lungs. 

Learn more: How Follow Alice keeps you safe on Kilimanjaro

Asthma is a chronic lung condition characterised by inflammation and narrowing of the airways, leading to breathing difficulties. During an asthma attack, the muscles around the airways tighten, the lining becomes inflamed, and excess mucus develops, obstructing airflow. Common symptoms include wheezing, shortness of breath, chest tightness, and persistent coughing. Common asthma triggers include allergens such as pollen and pet dander, physical exertion, cold air, stress, and respiratory infections. Asthma severity can range from mild, with occasional symptoms, to severe, where symptoms are persistent and debilitating. Asthma treatment often involves bronchodilators, also known as rescue inhalers, for acute symptoms and corticosteroids to reduce inflammation.

A change of scenery is often a welcome break. But for people with asthma, spending time in a high-altitude environment can cause unexpected effects. High altitude (typically considered above 2,500 metres) presents a unique set of challenges for people with asthma. At this elevation, the percentage of oxygen in the air is the same as at lower altitudes, 21%, while the atmospheric or barometric pressure decreases, and your body has to work harder to breathe. For anyone at a high altitude, it will be difficult to breathe at high altitude, not just if you have asthma. Higher altitudes tend to have cooler air temperatures and reduced oxygen, which can make asthma worse. These factors can lead to increased respiratory rate and dehydration of the bronchial lining, which may trigger asthma symptoms.   Intense physical activity, often part of high-altitude adventures, can also exacerbate asthma, making it even more challenging to manage. For travellers, it's important to understand that it's not the elevation change that triggers asthma symptoms; it's the change in air temperature and humidity. Our lungs like the air to be warm and humid. Cold, dry air is an irritant and can trigger asthma symptoms. The higher you go, the colder the air gets. When your respiratory system tries to adapt to high altitude, this can lead to aggravation of asthma symptoms. Reduced humidity, however, may prove beneficial for those with allergic asthma. Asthma symptoms can be triggered or worsened at high altitudes due to lower oxygen levels, cold air, and increased physical exertion. Some studies suggest that high altitudes could benefit those with well-controlled asthma, thanks to lower levels of allergens like dust mites and pollen. 

But don't be fooled – rushing up without proper acclimatisation can ramp up the risk of asthma flare-ups and altitude sickness, turning your adventure into a real challenge. This translates that the difficulty in breathing at higher altitudes is not affected by a lower percentage of oxygen in the air (which stays at 21% at all altitudes). Instead, the atmospheric pressure decreases as you go higher, which reduces the "driving force" for oxygen to enter your lungs. This lowered pressure makes it harder for oxygen to move into your bloodstream, causing you to breathe more heavily and work harder to get enough oxygen. Higher elevations also bring colder temperatures, not just during the cold winter months. This is a factor that is also often a trigger for many asthmatics. The freezing temperatures, along with the extremely dry air, can be a horrible combination. The dry, cold air can dry out the mucus membranes in the lungs, which are the body's natural defence mechanisms and can cause increased allergy symptoms for those with allergic asthma. Even for asthmatics without allergies, the cold, dry air can be a pretty significant trigger.

It's not all dull and gloom; not everyone with asthma will have an issue at a higher elevation. Your lungs may enjoy the cleaner air. With reduced air pressure at high altitude, the air is thinner, and there is less available oxygen for you to breathe. Air temperature and humidity also tend to be lower at high altitudes. Some asthmatics will find their asthma gets better the higher they are in elevation. There is less air pollution, which means you're breathing cleaner air, which makes the lungs very happy. Another perk is that when you get higher in elevation, there are fewer indoor living allergens, such as dust mites, which don't do well the higher you go. The vegetation also changes as the elevation increases, which can mean good news to some asthmatics (depending on their allergic triggers). Studies have shown that living at high altitudes can have great effects on health, including lower rates of allergies to house dust mites compared to people living at sea level. The findings suggest that living at high altitude can be beneficial for people with asthma, especially for those who need steroids to manage their condition. As always, if you are planning a trip to areas that have a higher altitude than you are used to when it comes to altitude, make sure you are prepared, especially if it is a place you have never been to before. It is important to talk with your doctor and update your asthma action plan before taking your trip. Remember to keep your rescue inhaler, a nebuliser and be sure to take your preventative asthma medications as scheduled. Also, take note of the closest hospital/medical facility “just in case.” 

Learn more: A guide on Kilimanjaro altitude sickness

High-altitude pulmonary edema (HAPE) is a severe, potentially life-threatening condition that occurs when fluid builds up in the lungs. It makes you cough and get out of breath quickly. HAPE can get worse fast and is fatal if not treated quickly. If you’re at high altitudes and have symptoms of HAPE, it's imperative to seek immediate medical attention and move to a lower altitude. It usually affects climbers and trekkers who ascend too quickly without allowing time for acclimatisation. Symptoms include severe shortness of breath, a dry cough that may progress to frothy, pink sputum, chest pain, fatigue, and cyanosis (bluish skin). These symptoms can be mistaken for severe asthma, complicating diagnosis.

A woman who suffers from asthma uses her inhaler

Inhalers deliver medication to the lungs through inhalation. The delivery method varies by type of inhaler, like the medication itself. Generally speaking, inhalers help manage asthma symptoms over the long term to alleviate symptoms during an asthma attack. Talk to your doctor to determine which inhaler is best for you. In many cases, a doctor will prescribe an albuterol inhaler for exercise-induced asthma. Albuterol is a bronchodilator that helps open and promote airflow through the lungs’ bronchial tubes to prevent and relieve coughing and wheezing, and help you breathe. If an albuterol inhaler isn’t working for you, your doctor may prescribe a different medication. Inhalers remain effective at high altitude, but cold temperatures can reduce the efficiency of metered-dose inhalers (MDIs) due to decreased propellant pressure. Keeping inhalers warm by storing them in an inner pocket helps maintain their functionality. Dry powder inhalers (DPIs) may be less affected by cold, but can still be compromised if exposed to moisture. DPIs that rely on aerodynamic forces to break up particles may require an increased inhalation flow rate to achieve nominal deposition at higher altitudes. Patients must understand that environmental conditions in which they use their inhaler can prevent ideal drug delivery. MDIs should ideally be acclimatised to room temperature. If this is not possible, DPIs (dry powder inhalers) may be a better option for use in cold (subzero) temperatures. 

Using an inhaler correctly can make a big difference in managing asthma, especially when climbing high altitudes. Proper technique ensures you get the full dose of medication, helping to keep symptoms under control. Here are some practical tips to make the most of your inhaler and help make breathing easier:

Here are some ways to manage anyone who has asthma during high-altitude climbs:

Learn more: What to pack for Kilimanjaro

Good preparation is important for travelling safely with asthma. Visit your doctor well before the trip to discuss your asthma plan. You may need increased doses of preventive medication. Consider carrying a portable oxygen machine, especially if you are planning intense activities. A quick chat with your doctor can help you identify any specific risks related to your destination, like pollen exposure or air pollution levels. You can also discuss whether you might need to adjust your asthma management while you’re away. If you’re travelling overseas, you should also carry a copy of your prescription or a letter from your doctor outlining what your medicine is, the required dosage and that it is for personal use. Follow the specific advice related to the medicine you take if you are prescribed a monoclonal antibody.

When you pack, start by making sure you have enough asthma medicine, including relievers and preventers, to cover your trip plus a few extra days. It is best practice to always use a spacer with your puffer, so remember to pack one of those, too! Collapsible asthma spacers may be useful and can also store your puffer inside. If you’re packing extra light, a cardboard spacer is also an option. Keep your medicines with you on the plane to avoid being without them if your luggage is lost or delayed. If you’ve been diagnosed as having asthma, keep an inhaler handy when backpacking, regardless of how long it’s been since your last attack, and give a backup inhaler to your hiking partner. The few measly ounces it will add to your pack weight could mean the difference between life and death. Breathing techniques can also help manage symptoms. Practice slow, deep breathing exercises to maintain control of your breath when physical exertion becomes demanding.

Here’s a handy checklist of what to pack:

If you have severe asthma, your respiratory specialist might also recommend taking an emergency supply of oral steroids with you, just in case. If you have allergies, make sure you always have your allergy medicine and/or epinephrine auto-injector with you.

Don’t forget to take travel insurance and make sure it covers high-altitude emergencies. Travel insurance that covers asthma-related medical costs is a must. Check your coverage for emergency treatment and, where possible, identify hospitals or healthcare facilities near your destination in case of a flare-up. See a doctor before hitting the trail if you notice any changes in your breathing.

A couple walking together

Learn more: How to climb Kilimanjaro sustainably and responsibly

Asthma doesn’t have to get in the way of your adventures. With a bit of planning and the right mindset, you can take on the world, whether that means climbing mountain peaks or exploring ancient sites at high altitudes. Just listen to your body, stay on top of your asthma management, and don’t let anything stop you from making amazing memories.

Being well-prepared is key when you're travelling. Make sure you have an updated action plan from your doctor and check if your medication needs any adjustments, especially if you're heading to places with different climates or high altitudes. When flying, keep your inhalers and meds in your carry-on so they’re easy to access. It’s also smart to carry a doctor’s note explaining your condition and prescriptions, in case airport security has any questions. To be extra cautious, label your meds clearly and pack a spare set in a separate bag, just in case your luggage gets lost.

Remember, your asthma triggers can change depending on where you are in the world. In cities, air pollution might be a problem, while rural areas could bring more pollen, dust, or altitude changes. Before you go, research the local air quality and weather, and consider bringing an air purifier if you'll be spending time indoors. When booking accommodation, look for places that are asthma-friendly, and think about non-smoking rooms with good ventilation. If you're heading to an area with lots of dust or allergens, packing hypoallergenic bedding or pillow covers can help reduce exposure. Simple steps like wiping down surfaces with sanitised wipes and airing out your room when you arrive can make a big difference in your comfort, too.

Dehydration can make asthma worse, especially at high altitudes or while flying. To stay hydrated, carry a reusable water bottle and drink regularly. Eating balanced meals with lots of fruits and vegetables helps boost your immune system, lowering the risk of respiratory infections. Avoid alcohol and caffeine, as they can make dehydration worse. If you’re planning on doing a lot of physical activity or spending time at high altitudes, it’s a good idea to pack electrolyte tablets or drinks to stay balanced.

Keep an eye out for early asthma symptoms like wheezing, shortness of breath, or chest tightness. If you have a peak flow meter, use it regularly, and follow your asthma action plan if things start to worsen. Pay attention to how your body reacts to changes in the environment, your activity levels, or the altitude, and take breaks when needed. Even with all your planning, emergencies can happen, so it’s important to know where the nearest medical facilities are. Always carry your meds and emergency contact info with you, and think about getting travel insurance that covers pre-existing conditions like asthma. You might also want to download apps that provide real-time air quality updates or show nearby medical facilities, especially if you're travelling abroad.

High-altitude travel has its rewards, but it does require a bit more caution. Take your time to adjust to the thinner air by ascending slowly, staying hydrated, and pacing yourself. Before your trip, getting in good shape with activities like walking, cycling, or swimming can help improve your lung capacity and make it easier to handle the altitude. If you’re going on a guided trek, let your guide know about your asthma so they can offer support if needed. Taking short, regular breaks and practising some controlled breathing can also help reduce the strain on your lungs at high altitudes.

Asthma doesn’t have to stop you from exploring the world’s most incredible places. With the right preparation and a proactive approach to managing your condition, you can safely explore high-altitude adventures and create memories that will last a lifetime. Yes, there will be challenges, but with the right planning, you can conquer them. Understanding how your body responds to higher elevations and staying on top of your asthma will help you enjoy the stunning views and outdoor experiences to the fullest. Listen to your body, follow your doctor’s advice, and take the necessary steps to keep your journey safe and enjoyable. Travelling with asthma is all about finding that sweet spot between being cautious and being curious by staying prepared and mindful, you can embrace new adventures without compromising your health.