Swallowing a bug is almost always harmless. Your stomach acid will kill and digest most insects the same way it handles food, and the bug will pass through your system without causing any problems. The momentary disgust is usually the worst part of the experience.
That said, there are a few uncommon situations where swallowing an insect can cause real trouble. Here’s what to know and when to take action.
Why Most Bugs Are Harmless to Swallow
Your digestive system is remarkably hostile to small organisms. Stomach acid, which sits at a pH between 1.5 and 3.5, breaks down insect exoskeletons just like it breaks down other proteins and fibers. A small fly, gnat, or mosquito that ends up in your mouth while you’re cycling, running, or eating outdoors will be dissolved and absorbed like any other food particle. Humans around the world eat insects intentionally, from crickets and mealworms to grasshoppers and ants, with no ill effects.
If you’ve swallowed a common household bug, a gnat, or a small flying insect, the best thing to do is drink a glass of water to help wash it down and move on with your day.
When a Swallowed Bug Could Be a Problem
Stinging Insects
Bees and wasps are the main concern. If a bee or wasp stings the inside of your mouth, throat, or esophagus on the way down, the tissue can swell rapidly and potentially obstruct your airway. This is dangerous regardless of whether you have an insect allergy. Signs to watch for include a tight feeling in your throat, difficulty swallowing, difficulty breathing, or noticeable swelling in your mouth or tongue. If any of these develop, call 911 immediately.
People with known bee or wasp allergies face an additional risk of a full-body allergic reaction. Symptoms include hives, dizziness, a fast pulse, stomach cramps, nausea, and swelling beyond the sting site. If you carry an epinephrine auto-injector, use it and still call emergency services.
Blister Beetles
Blister beetles produce a chemical called cantharidin that can irritate and damage tissue. The amount of cantharidin per beetle ranges from 0.2 mg to nearly 5 mg depending on the species. Even small amounts can cause severe symptoms in children, including vomiting blood, abdominal pain, and kidney problems. The estimated fatal dose in adults is roughly 1 mg per kilogram of body weight. Blister beetles are elongated, soft-bodied beetles often found in gardens and crop fields. Swallowing one accidentally is rare, but if you suspect it happened (especially in a child), contact poison control or go to an emergency room.
Allergic Reactions to Insect Proteins
If you have a shellfish allergy or a dust mite allergy, you may be more likely to react to insect proteins. Insects share a protein called tropomyosin with shrimp, crab, and dust mites, and this cross-reactivity can trigger allergic symptoms ranging from hives to more serious reactions. This is uncommon with a single accidentally swallowed bug, but worth knowing if you have these allergies and notice any unusual symptoms afterward.
What About Parasites?
A condition called intestinal myiasis can occur when fly eggs or larvae deposited on food are swallowed and survive inside the gastrointestinal tract. According to CDC reports, some people with this condition experience abdominal pain, vomiting, and diarrhea, while others have no symptoms at all. However, most fly larvae that are accidentally ingested cannot survive in the acidic environment of the gut. They die and pass through in stool without ever establishing a real infestation. This scenario is far more associated with contaminated food than with swallowing a single flying insect.
If the Bug Feels Stuck
Larger insects, or parts of them, can occasionally feel lodged in your throat. This is more likely a sensation caused by a scratch or mild irritation on the lining of your throat than an actual obstruction. Try drinking water or a carbonated beverage. The bubbles in soda or sparkling water can help dislodge material stuck in the esophagus. Eating a piece of soft bread can also help push things along.
If you genuinely cannot swallow, are drooling, or feel like something is blocking your airway, that’s a choking situation. Foreign objects longer than about 6 cm or wider than 2 cm are more likely to cause obstruction, which is well beyond the size of most insects you’d accidentally swallow. Still, if you feel a persistent blockage or have chest pain after swallowing, seek medical attention.
Managing the Disgust Factor
The nausea you feel after swallowing a bug is almost certainly psychological rather than physical. Your brain registers the event as disgusting and triggers a gag reflex or queasy feeling, even though your stomach is handling the situation just fine. Sipping water, taking a few slow breaths, and reminding yourself that the bug poses no real danger can help the sensation pass. Do not try to make yourself vomit. Forcing vomiting risks injuring your esophagus and is unnecessary for something your digestive system will process on its own.
Symptoms That Need Immediate Attention
For the vast majority of accidentally swallowed bugs, no medical care is needed. But call 911 or go to an emergency room if you experience any of the following within minutes to hours afterward:
- Difficulty breathing or a tight feeling in your chest
- Swelling of your tongue, throat, or lips
- Hives or widespread rash
- Dizziness or lightheadedness
- Severe abdominal pain or vomiting blood
- Difficulty swallowing that doesn’t resolve with water
These reactions are rare. If 30 minutes have passed and you feel fine other than mildly grossed out, you’re in the clear.