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What Happens When You Swallow a Bug

We’ve all been there: You’re out on a run or a bike ride, and you swallow a bug. After the initial sensations of shock and disgust, you may be left wondering: What happens now? To me? To the bug?
 
Let’s look at the potential outcomes of accidentally consuming an insect. 
 

Digesting an Insect 

 
Swallowing your run-of-the-mill bugs like spiders, gnats, mosquitoes, etc. isn’t likely to do you any harm. Your body digests them the same as any other protein-rich food, according to Dr. Bobbi Pritt, MD, FCAP, a microbiologist, pathologist, and director of the clinical parasitology laboratory at Mayo Clinic.
 
“Eating a bug now and then probably won’t be a problem for most,” Dr. Pritt says.
 
An exception is insects like flies, which often carry the bacteria Shigella on their feet. Shigella causes severe and, frequently, bloody diarrhea in humans. 
 
“If this happens, it usually resolves itself within a week, but if it’s severe, it may require antibiotics,” Dr. Pritt says.
 

More Severe Cases 

 
Much more problematic are bees, wasps, fire ants, and the like. These types of insects can do damage to your mouth and throat if they manage to sting or bite on the way down.
 
“Usually eating one will just cause mild pain and localized swelling if it bites or stings you,” Dr. Pritt says. 
 
However, throat irritation can cause breathing difficulty, especially for people with asthma, and an internal bite or sting can be life-threatening if you’re allergic. 
 

What Happens to the Bug

 
The outlook is much bleaker for the bug, as you might expect. If both you and the bug are fortunate, it will be coughed out and hopefully not too worse for the wear. If fully swallowed, though, there’s little to no chance of survival; the human digestive system is not a hospitable environment. However, some bugs, such as certain types of beetles, have evolved to survive ingestion, if swallowed whole.