Traveling by air can cause or worsen a variety of medical conditions, although very few conditions would prevent a person from flying. Those that may prevent flying include a pneumothorax, lung damage from tuberculosis, diseases that could be spread to other passengers, and conditions in which even a small expansion of air would damage tissues, such as intestinal surgery in the previous 10 days.
Some conditions require planning and taking precautions before a flight.
For example, people who have had a colostomy should wear a large bag and anticipate frequent filling. This expansion sometimes aggravates certain medical conditions, such as emphysema, blocked eustachian tubes, chronic sinusitis, and chronic gas pains. Problems may be particularly severe when an airplane accidentally loses cabin pressure or when the cabin isn't pressurized, as is the case with some smaller airplanes. A sensation of pressure in the ears is common during airplane flights. It develops as the difference between pressure outside the ear and inside the ear increases, causing the eardrum to bulge.