emetic
Meaning of emetic: Anything that brings on vomiting, whether given deliberately, produced by a disease, or arriving as a side effect.
Definition of emetic
An emetic is a substance that causes vomiting. Some act on the stomach lining directly, while others act on a region of the brainstem that monitors the blood for toxins and triggers the vomiting reflex. The word also functions as an adjective describing that property, as in the emetic effect of a drug.
How is vomiting triggered?
Vomiting is a coordinated reflex run from the brainstem, not a simple stomach event. Several separate inputs can set it off, which is why substances with nothing in common can all be emetic.
| Trigger route | What activates it |
|---|---|
| Chemical sensor in the brainstem | Toxins and drugs carried in the blood |
| Gut nerve signals | Irritation or stretching of the stomach and bowel |
| Balance organs of the inner ear | Motion, and inner ear disease |
| Higher brain centers | Smell, sight, pain, anticipation |
Are emetics used as treatment?
Rarely now. Syrup of ipecac was once kept in homes and given after a poison was swallowed, on the reasoning that bringing the substance back up would limit harm. It fell out of standard practice: the amount recovered proved small, vomiting delayed treatments that work better, and some swallowed substances cause more damage coming up than going down. Deliberate emetics survive mainly in veterinary practice and in a few specialized settings. Apomorphine, a drug acting on the brainstem sensor, is the usual agent where one is used at all.
What does emetogenic mean?
Most modern use of these words runs the other way, describing an unwanted effect rather than a desired one. A drug called emetogenic is one likely to provoke vomiting as a side effect, and chemotherapy drugs are ranked by how strongly they do so. That ranking guides which anti-sickness medicines are given alongside them. The opposite of an emetic is an antiemetic, a drug that suppresses the reflex, and the two words share the same root.
Also known as
Used in a sentence
The agent is highly emetic and was given with anti-sickness cover.
Good to know
Emetics are no longer part of routine poisoning management, and the related word emetogenic is now used mainly to rank how strongly a treatment provokes vomiting as a side effect.
Word origin
Where “emetic” comes from
From the Greek emetikos, provoking sickness, from emein, to vomit.