Why snoozing through these specific parts of a flight is bad for your health

Sleeping is sometimes the only way to get through a long flight—you can only binge-watch so many consecutive episodes of Gilmore Girls, after all (unless, of course, you drink as much coffee as the show’s main characters). But if you tend to doze off before you even jet off the runway, you might want to rethink your in-flight snoozing habits.

You know how a quick shift in altitude makes your ears feel like they need to pop? According to MedlinePlus—a health site run by the US National Library of Medicine—this sensation occurs when the air pressure inside your middle ear and outside of your eardrum don’t match.

When you’re awake during the takeoff or landing of a flight, you’ll feel the pressure immediately and adjust by yawning, swallowing, or chewing gum to open the eustachian tube and make the airflow return to normal.

But if you’re asleep during a change in altitude and unable to equalize the pressure in your ears, you could sustain permanent damage.

If you’re asleep during a change in altitude and unable to equalize the pressure in your ears, you could sustain serious damage.

In mild cases of this condition, known as ear barotrauma, you can experience pain and muffled sounds that will go away on their own. But in more severe cases that last for more than a few hours, fluid may end up behind the eardrum as the body tries to equalize the pressure itself, according to Harvard Medical School, which can lead to pain and hearing difficulties. The eardrum can also break, causing blood or fluid to leak from your ear, or you could end up with a deep leak called a fistula, which can make you feel like you’re spinning or falling.

If you think you’ve experience barotrauma after a flight and the symptoms aren’t going away, call your doctor—severe cases might require surgery. And if you’re flying with a cold, ear infection, or allergies, it’s recommended that you either reschedule your flight or take a decongestant before traveling to help ensure your eustachian tubes stay open.

So be outgoing, and ask a flight attendant or your seat neighbor to wake you if you’re still fast asleep prior to landing. Your future self will thank you, and you might even make a new friend.

Jessica Chastain says this inexpensive cream is her in-flight savior. And if you tend to get stressed while traveling, keep these essential oils on hand.