Eye drops are meant to be used directly on the eyes, but they may sometimes be misused and administered with other methods, intentionally or unintentionally. Putting eye drops in a beverage can cause the person who drinks it some severe side effects. The active ingredient in some medical eye drops can cause symptoms such as nausea and vomiting. A severe drop in blood pressure and body temperature could also occur, and a person could even slip into a coma and die.
One of the most popular urban legends involves eye drops in a drink. The legend states that if a victim ingests just a couple drops of this eye medicine, he will suffer from diarrhea for a few hours. This urban legend has often been popularized by the media, showing up in various movies.
Regular saline eye drops will not typically have any effect on a person, if ingested. Only medical eye drops designed to minimize red eyes will cause problems when they are ingested. These typically contain an active ingredient known as tetrahydrozoline, which helps constrict blood vessels.
Ingestion of tetrahydrozoline via eye drops in a drink can cause severe nausea, but not usually diarrhea. Vomiting, on the other hand, is common in people who ingest this substance. Blurred vision and tremors can also occur. It usually only takes a couple of drops to cause these symptoms, though larger amounts can cause much more serious problems.
Tetrahydrozoline can also cause other, more serious, problems. The blood pressure of a person who ingests eye drops in a drink can possible rise and drop suddenly. His body temperature may also drop to dangerously low levels. Seizures can also occur, and a person may even slip into a coma. If left untreated, ingesting eye drops may even prove fatal.
Putting eye drops in a drink is not just harmless fun. After seeing it on movies or hearing about it through the grape vine, some people have even tried it. Some have given eye drops to friends as a joke, while others have tried to make their enemies uncomfortable.
In the United States, putting eye drops in a person's drink is considered attempted poisoning. This is a serious crime with some serious repercussions. Some defendants may even get jail time for an offense that began as a supposedly harmless prank.