Flying can make some people feel unwell because the air pressure inside the plane is lower than it is on the ground. During a flight, the cabin pressure is usually similar to being on a mountain between 1,500 and 2,400 meters above sea level. This means there is slightly less oxygen in the air.
Because of this, some people may feel tired, dizzy, short of breath, or get a headache. Other common symptoms include blocked ears, bloating, and dehydration. Most healthy people only have mild symptoms, but people with heart problems, lung conditions, sinus issues, or anxiety may feel worse.
Modern planes are designed to maintain a safe cabin pressure, but they do not make it feel exactly like being at ground level. As the plane goes higher, changes in air pressure can affect your ears, sinuses, digestion, and blood flow. The air inside the cabin is also very dry, which can make you thirsty and tired, or cause a sore throat on longer flights.
According to the European Union Aviation Safety Agency, most commercial planes keep cabin pressure at a level equal to no more than 8,000 feet above sea level. This is considered safe for healthy passengers.
For most people, these symptoms last only a short time and usually improve a few hours after landing. Knowing how cabin pressure works can help you prepare better, especially if you are flying with a cold, breathing problem, poor circulation, or often get ear pain on planes.
What Is Cabin Pressure on a Plane?
Cabin pressure is the air pressure inside a plane during a flight. Planes fly very high, often more than 10,000 metres above the ground. At that height, the air outside is too thin for people to breathe properly.
To keep passengers safe, planes are pressurised so there is enough oxygen in the cabin. However, the cabin does not feel the same as being at sea level. Most planes are pressurised to simulate being at between 1,500 and 2,400 metres above sea level.
This means there is slightly less oxygen in the air than your body is used to on the ground. Most healthy people can cope with this without any serious problems.
Lower cabin pressure can cause gases in the body to expand. This is why people often experience ear blockages, sinus pain, bloating, or trapped wind during take-off and landing. Some people may also feel tired, dizzy, light-headed, or short of breath.
The biggest pressure changes happen when the plane takes off and lands. As the plane climbs, the air pressure drops. This can cause pressure in the ears and sinuses. When the plane lands, the pressure changes again, and this is often when ear pain feels worse.
People with colds, allergies, sinus infections, or blocked noses may find it harder to adjust to these changes.
According to the European Union Aviation Safety Agency, cabin pressure on planes is kept within safe limits for passengers and crew. This helps prevent serious health problems, even though mild symptoms can still happen.
Why Can Flying Make You Feel Ill?
Flying can affect your body in different ways, even if you are healthy. Lower oxygen levels, changes in cabin pressure, dry air, sitting still for long periods, and time zone changes can all make you feel unwell during or after a flight.
Some people have only mild symptoms, while others may feel much worse depending on their health, age, and the length of the flight.
Lower Oxygen Levels Can Make You Feel Tired
One reason people feel tired after flying is that the cabin has slightly less oxygen than the ground. Your body has to work a little harder, especially on longer flights.
This can cause:
- Tiredness
- Mild dizziness
- Headaches
- Trouble concentrating
- Shortness of breath
- Feeling weak or light-headed
Most healthy people cope well, but people with asthma, heart disease, lung conditions, or anaemia may notice these symptoms more.
Cabin Pressure Can Cause Ear Pain and Blocked Ears
Ear pain is very common when flying. This happens because the pressure inside your ears needs to match the cabin pressure. During take-off and landing, the pressure changes quickly, and your ears may struggle to adjust.
This can cause:
- Popping ears
- Ear pain
- A blocked feeling
- Muffled hearing
- Temporary dizziness
People with colds, allergies, sinus infections, or blocked noses may have worse symptoms.
Swallowing, yawning, chewing gum, or sucking sweets can help your ears adjust during take-off and landing.
Dry Cabin Air Can Make You Dehydrated
The air inside a plane is very dry. This means your body can lose moisture more quickly.
This can cause:
- Dry mouth
- Dry eyes
- Chapped lips
- Sore throat
- Headaches
- Tiredness
Drinking water during the flight can help. It is also a good idea to avoid too much alcohol or caffeine, because these can make dehydration worse.
Flying Can Cause Bloating and Stomach Pain
Changes in air pressure can also affect your stomach. Gas inside the stomach and intestines expands during a flight, which can make you feel bloated or uncomfortable.
This can cause:
- Bloating
- Trapped wind
- Stomach cramps
- A full feeling
These symptoms can be worse if you eat a heavy meal before flying or drink fizzy drinks.
To help prevent this:
- Avoid large meals before flying
- Drink water
- Avoid too many fizzy drinks
- Eat lighter foods
- Walk around when you can
Jet Lag Can Affect Sleep and Mood
Jet lag happens when you travel across different time zones. Your body clock can become confused when the local time differs from what your body is used to.
Jet lag can cause:
- Poor sleep
- Tiredness during the day
- Trouble concentrating
- Feeling grumpy
- Mood changes
- Digestive problems
- Less appetite
Jet lag is often worse when travelling east because your body has less time to adjust.
Long Flights Can Affect Blood Flow
Sitting for long periods can slow blood flow in your legs. This can make your feet, ankles, and legs swell.
On flights longer than four hours, there is also a small risk of a blood clot in the leg, called deep vein thrombosis, or DVT.
The risk is higher for people who:
- Are pregnant
- Smoke
- Are overweight
- Had surgery recently
- Are older
- Had blood clots before
- Take hormone replacement therapy
- Take the contraceptive pill
Most people will not get a blood clot from flying, but it can help to stretch your legs, walk around when possible, and wear loose clothing.
|
Cause |
What happens |
Common symptoms |
|
Lower oxygen levels |
Your body gets slightly less oxygen than on the ground |
Tiredness, dizziness, headache, shortness of breath |
|
Cabin pressure changes |
Pressure affects the ears, sinuses, and gas in the body |
Blocked ears, ear pain, sinus discomfort, bloating |
|
Dry cabin air |
The body loses moisture more quickly |
Dry mouth, dry eyes, sore throat, tiredness |
|
Sitting still for too long |
Blood flow slows down in the legs |
Swollen feet, leg discomfort, higher DVT risk |
|
Time zone changes |
Your body clock gets out of sync |
Poor sleep, fatigue, mood changes, digestive problems |
Who Is More Likely to Feel Unwell During a Flight?
Most people can fly safely without any serious problems. However, some people are more likely to feel unwell due to lower oxygen levels, changes in cabin pressure, and prolonged sitting.
People with Breathing Problems
People with breathing conditions may find flying harder because there is less oxygen in the cabin.
Conditions that may cause problems include:
- Asthma
- Chronic obstructive pulmonary disease, also called COPD
- Sleep apnoea
- Pulmonary fibrosis
- Severe allergies
- Recent chest infections
People who use oxygen therapy or have serious breathing problems should speak to a doctor before flying. Some airlines may ask for a medical letter or notice in advance if oxygen is needed during the flight.
People with Heart Problems
Flying can put extra strain on the heart due to lower oxygen levels, mild dehydration, and prolonged sitting.
People with the following conditions may need to be more careful:
- Heart failure
- Coronary heart disease
- Angina
- A recent heart attack
- High blood pressure
- Irregular heart rhythms
People who have recently had heart surgery or a heart problem should speak to a doctor before travelling.
People with Ear, Sinus, or Dental Problems
People with colds, blocked noses, sinus infections, or ear infections may feel much more pain during take-off and landing.
Conditions that can make flying more uncomfortable include:
- Colds
- Sinus infections
- Ear infections
- Hay fever
- A blocked nose
- Recent dental treatment
Some people may also get tooth pain during a flight if they have a cracked tooth, a cavity, or recent dental work.
Pregnant Women and Older Adults
Pregnant women and older adults may be more likely to feel tired, swollen, or uncomfortable during a flight.
Sitting still for long periods can increase the risk of swollen legs and blood clots, especially on flights longer than 4 hours.
Most airlines allow pregnant women to fly during most of their pregnancy, but some may ask for a medical letter in the later pregnancy.
Older adults may also be more affected by dehydration, lower oxygen levels, and prolonged sitting.
People Recovering from Surgery or Illness
Flying too soon after surgery or a serious illness can sometimes make recovery harder.
People should be careful about flying after:
- A recent hospital stay
- Pneumonia
- Severe flu
- A blood clot
- Deep-sea diving in the last 24 hours
- Major dental work
Flying may also be more difficult after stomach, chest, or eye surgery, or any operation where gas may still be trapped inside the body.
This is because gas expands at higher altitudes, which can worsen pain and slow healing.
Symptoms After Flying That Should Not Be Ignored
Most symptoms after flying are mild and get better within a few hours. Feeling tired, having a mild headache, bloating, dry eyes, and blocked ears are all common after a flight.
However, some symptoms can be more serious and should not be ignored, especially if they persist or worsen.
Warning signs include:
- Severe shortness of breath
- Chest pain
- Fainting
- Ongoing dizziness
- Confusion
- Blue lips or fingertips
- Swelling in one leg
- Severe pain in the calf
- Coughing up blood
- A high fever after travel
- Severe ear pain
- Hearing loss
- Ongoing vomiting
Chest pain, trouble breathing, or swelling in one leg can be signs of a blood clot. This can be very serious and needs urgent medical help.
A swollen and painful calf after a long flight should not be ignored, especially if it happens with chest pain or shortness of breath.
Severe ear pain, bleeding from the ear, or sudden hearing loss can occur due to pressure changes during the flight. This is more common if you fly with a cold, sinus infection, or blocked nose.
Ongoing dizziness, fainting, or confusion after flying may be caused by dehydration, low oxygen levels, poor blood flow, or another health problem.
People with heart disease, lung disease, or diabetes should be extra careful if symptoms continue after landing.
If you have serious symptoms after flying, especially breathing problems, chest pain, or swelling in the legs, you should get medical help as soon as possible.
How to Reduce the Chances of Feeling Ill When Flying
Most people can reduce cabin pressure symptoms by taking a few simple steps before, during, and after a flight. This can help with dehydration, blocked ears, bloating, tiredness, and poor circulation.
Before Your Flight
What you do before flying can make a big difference.
Helpful tips before flying include:
- Drink plenty of water before you leave
- Avoid drinking too much alcohol the night before
- Have less caffeine if it makes you feel anxious or dehydrated
- Wear loose and comfortable clothes
- Avoid heavy or very salty meals before your flight
- Try not to fly if you have a bad cold, sinus infection, or ear infection
- Speak to a doctor before flying if you have heart disease, asthma, COPD, or have had blood clots before
- Keep medicines, inhalers, compression stockings, nasal sprays, or eye drops in your hand luggage
If you often get ear pain on planes, chewing gum, sucking sweets, or using a saline nasal spray before take-off may help.
During the Flight
Drinking water and moving around are two of the best ways to avoid feeling unwell on a plane.
During the flight, try to:
- Drink water regularly
- Avoid too much alcohol
- Move your feet and legs while sitting down
- Walk around the plane every one to two hours on longer flights
- Stretch your ankles and calves
- Wear compression stockings if you are at risk of swollen legs or blood clots
- Chew gum, yawn, or swallow during take-off and landing
- Use moisturiser, lip balm, or eye drops if the cabin feels very dry
- Avoid fizzy drinks and large meals that can make bloating worse
- Change your watch to the local time if you are on a long-haul flight
People who wear contact lenses may find their eyes become dry more quickly on a plane. Wearing glasses may feel more comfortable on longer flights.
After the Flight
After you land, your body may need a few hours to get used to normal air pressure and local time again.
After flying, it can help to:
- Keep drinking water
- Eat light meals if you feel bloated or sick
- Rest if you feel tired or jet-lagged
- Spend some time outside in daylight
- Stretch or go for a short walk
- Get back to your normal sleep and meal times as soon as possible
- Watch for unusual symptoms such as chest pain, trouble breathing, or severe swelling
Most people feel better quickly after a flight. Looking after yourself before, during, and after travelling can make flying much more comfortable, especially on long journeys.
Is Flying Safe for Most People?
Flying is safe for most people, including older adults, pregnant women, and people with stable health conditions.
Modern planes are built to maintain a safe cabin pressure and oxygen levels during flight. Even though the air pressure is lower than at ground level, most people only experience mild symptoms.
Common symptoms can include:
- Tiredness
- Headaches
- Bloating
- Blocked ears
- Dry mouth
- Mild dizziness
These symptoms are usually mild and often get better soon after landing.
Most healthy people only notice small changes during take-off, landing, or on long flights. Ear popping, feeling tired, and mild dizziness are all common and are usually nothing to worry about.
People with certain health conditions may need to prepare more before flying. This includes people with:
- Severe asthma
- COPD
- Heart disease
- Recent surgery
- A history of blood clots
These travellers should speak to a doctor before flying, especially before a long flight.
Some people may need medicines, compression stockings, or extra oxygen during the flight.
Most people with stable health conditions can still fly safely if they plan ahead and follow medical advice.
Understanding how cabin pressure works can help people feel more prepared and less worried before travelling.
Conclusion
Flying can make some people feel ill, but in most cases, the symptoms are mild, temporary, and caused by normal changes in cabin pressure, oxygen levels, dry air, and sitting still for long periods. Common problems such as ear blockage, headaches, fatigue, bloating, dehydration, and dizziness usually improve shortly after landing.
Understanding how cabin pressure affects the body can help you better prepare for your next flight. Simple steps such as drinking more water, moving regularly, avoiding heavy meals, and protecting your ears during take-off and landing can make a big difference.
Most people can fly safely without serious health concerns. However, if you have a heart condition, respiratory illness, recent surgery, or a history of blood clots, it is worth speaking to a healthcare professional before travelling. Paying attention to symptoms and knowing when to seek medical advice can help make flying more comfortable and less stressful.
If you are unsure whether you are fit to fly or you have concerns about symptoms before travelling, Mobi Doctor can help you speak with a licensed doctor online before your trip.
