Why do some people gag when someone is vomiting?

Dear Reader, 

You might’ve seen in a movie or tv show when one person vomits and sets off a domino effect of everyone in the room doing the same! Gagging when someone else vomits likely happens as a reaction to the sound, smell, and sight of someone else throwing up. Replaying the thoughts of the vomiting in your mind might also cause your body to react as if you were sick, too.  

Generally, gagging is an uncontrollable reflex that the body does to protect itself from something getting stuck in your throat, or in response to something you don’t like. You might gag while brushing your teeth, swallowing a large pill, or taking too large a bite of food. In addition to seeing someone else vomit, you may have a gag reflex in response to strong smells, tastes, or seeing something you find gross. 

What is a gag reflex? 

Biologically, the gag reflex causes the throat to tighten (contract) and the soft palate (the top back part of your mouth) to rise, which produces the gag response. This works quickly and without conscious control. Sensory nerves send signals to the brain, which then sends signals through motor nerves to the throat.  

What triggers the gag reflex? 

The gag reflex can be triggered physically (somatogenic) and psychologically (psychogenic). A somatogenic gag reflex happens through direct contact, like something touching the back of your throat. A psychogenic gag reflex is triggered from thoughts, emotions, or sensory experiences. 

Gagging at the sight of vomit is related to nausea and disgust. Nausea is the feeling that you might throw up, and disgust is an emotional response. These two responses can be linked together. For example, smelling vomit can trigger disgust which can lead to nausea. Nausea can lead to gagging or vomiting. It’s like a whole ripple effect being set off by a sensory trigger! 

Why do people need a gag reflex? 

The gag reflex prevents people from choking or swallowing unwanted objects. It also has evolutionary roots that have helped people avoid danger. For early primates , if one person ate something toxic and vomited, other people who saw or smelled the vomit would be alerted to the potential danger. For example, if one primate got sick after eating a bad berry, that might make others nauseous and avoid the berry, or it might make them vomit as well to get it out of their system. 

Developmentally, this reflex is the strongest when you’re an infant and becomes less sensitive over time. When babies are born, their bodies react strongly to food that is too large or difficult to digest. Around seven months, the gag reflex decreases, and they begin eating more solid foods. 

How can you manage your gag reflex? 

People’s gag reflex sensitivity can vary! Some people have a hypersensitive gag reflex, which means they react more easily or intensely. This can be linked to anxiety or acid reflux. Other people have a reduced or absent gag reflex. This seems to occur naturally, and it’s more common in those with a history of smoking or tobacco use. If someone’s gag reflex is very sensitive, they can work with a health care provider to help control this reaction. 

The gag reflex can be reduced using behavioral and medical techniques such as acupressure, anti-nausea medication, cognitive behavioral therapy, distractions, local anesthetics, and lower-level laser therapy.  

Although nausea, gagging, and vomiting aren’t usually serious, immediate medical attention is necessary in some situations. Suspected poisoning, vomiting for more than 24 hours, blood in vomit, severe abdominal pain, severe headache, severe stiff neck and signs of dehydration such as dry mouth, infrequent urination and dark urine are all reasons to immediately contact a medical provider. 

So next time you watch a comedy sketch where there’s a cascade of vomiting and you start to gag too, just know it’s your body doing its job! 

Don’t lose your lunch,