Stink bugs are known for releasing a foul-smelling defensive liquid when disturbed or crushed. Accidental ingestion often occurs when these small insects are hidden in produce like grapes or berries, or fall unseen into a beverage, which naturally causes concern. The primary reaction to swallowing a stink bug is an immediate, intense, and unpleasant sensory experience. This encounter is typically a defense mechanism gone wrong, as the insect’s protective chemicals are released inside the mouth or throat.
The Immediate Sensory Experience
The unpleasant sensation comes from a defensive spray the bug releases instantly upon being bitten or swallowed. This liquid is composed of volatile chemical compounds, primarily aldehydes and hydrocarbons, designed to repel predators. These compounds give the bug a distinctively acrid and bitter taste that is immediately noticeable.
The odor and flavor are often attributed to specific compounds like trans-2-octenal and trans-2-decenal, which are oily and strongly pungent. Because of these chemicals, the experience is not just a passing bad taste, but a lingering, irritating sensation that can cause the mouth and throat to feel mildly irritated.
Health Effects and Toxicity Assessment
The defensive secretions of most common stink bug species are not considered poisonous to humans. The compounds are highly irritating and distasteful, but they are generally not toxic in the small amounts released by a single insect. Once swallowed, the low pH of stomach acid and digestive enzymes quickly begin to break down the chemicals.
The most common physical reactions following accidental ingestion are mild and self-limiting, often involving gastrointestinal distress. People may experience mild nausea, temporary stomach upset, or an episode of vomiting, which is often a result of the body reacting to the irritating nature of the chemicals. Ingesting a single bug is overwhelmingly considered a harmless event for the vast majority of people. Rare reports exist of more severe symptoms, such as vertigo and tremors, but these cases are not typical for common accidental ingestion.
When Medical Attention Is Necessary
While the event is usually harmless, there are specific, rare circumstances where a medical consultation may be warranted. Seek professional attention if the person shows signs of a severe allergic reaction. These signs include difficulty breathing, significant swelling of the lips, tongue, or throat, or the development of hives across the body.
Medical advice should also be sought if mild gastrointestinal symptoms, such as vomiting or stomach pain, become severe, persist for more than a few hours, or worsen over time. Additionally, if an infant or a person with known severe chemical sensitivity consumes a stink bug, contact a poison control center or healthcare provider for guidance. These professionals can assess the situation based on the individual’s specific health profile.