## Infection There is a common belief that it is very easy to catch a [virus](https://ul.orna.me/KOge/librarydisease?id=32) on a plane, which is not entirely true. The air on the plane is much cleaner than on public transport, as it is controlled and purified by special filters. However, there is always the risk of catching the virus from the person sitting next to you if they are sick — especially during the [COVID-19](https://ul.orna.me/KOge/librarydisease?id=221) pandemic. ## Headache At high altitudes, a person may experience a mild form of hypoxia, as the oxygen level in the body decreases. To relieve discomfort and headache, you should drink plenty of water, periodically walk around the cabin, and refrain from coffee and alcohol during the flight. ## Tinnitus and hum Most passengers get stuffy ears and experience a buzzing sound during take-off and landing due to the change in atmospheric pressure. This occurs because the pressure in the eardrum does not have enough time to equal the atmospheric pressure. To reduce the discomfort, you can chew candy or gum, drink water in small sips, or yawn. If there is nothing wrong with the ears, and no diseases, then flying on a plane is not a threat, and unpleasant sensations will quickly pass. Children are allowed to fly in the first months of life if there are no contraindications. Your baby may be given a bottle of water or a pacifier to make take-off and landing easier. ## Toothache People who have cracked enamel or cavities are at risk, as the drop in pressure can provoke a toothache. A painkiller will help, but it's better to visit a dentist before the flight. ## Poor circulation, venous thrombosis, and edema Prolonged sitting in a sedentary position causes blood stagnation, which leads to edema and venous thrombosis. To avoid this, try to walk around the plane cabin. If this is not possible, do simple exercises for the legs including circular foot movements, bending and unbending the knees, rising from the seat and sitting back down, and massaging the calves. These exercises will help to restore blood circulation. Pregnant women and people who suffer from varicose veins, cardiovascular diseases, high blood clotting, or edema are advised to fly in compression stockings. It is better to put them on before the flight, with the legs elevated for about 30 minutes before the flight. ## Dehydration During the flight, the air in the cabin is highly discharged, as it undergoes a certain treatment. Such air provokes rapid dehydration, so you should drink as much water as possible during the flight. The lack of moisture on a plane can cause a dry nose and eyes, so you should carry moisturizing eye drops and nasal spray. ## Biorhythm disturbance During long flights — especially if you change time zones — your circadian rhythms (biorhythms) may be disrupted. Our internal clock affects how our body functions, which includes hunger, sleepiness, synthesis of hormones, etc. The body needs 24 hours for adaptation for each hour of difference. Staying in the sunlight and fresh air after landing will help you to recover faster. ## Groups not advised to fly Some people are not advised to fly on planes. This includes people with infectious diseases, [pneumonia](https://ul.orna.me/KOge/librarydisease?id=216), decompression sickness after diving, deep vein thrombosis of the legs, high intracranial pressure, severe chronic respiratory diseases, shortness of breath at rest, [sickle cell anemia](https://ul.orna.me/KOge/librarydisease?id=64), unresolved pneumothorax, psychosis, or who have recently experienced [myocardial infarction](https://ul.orna.me/KOge/librarydisease?id=89) or stroke. Additionally, infants under 2 days old and women who are 36 or more weeks pregnant should not fly.