Body and drug basics
Antagonist
Last updated
An antagonist attaches to a receptor without switching it on, and by sitting in the way it stops the body's own molecule from getting in. It is a key that fits the lock but does not turn it, and blocks the keyhole for as long as it stays. The result is less of whatever that receptor normally produces.
Why it matters here
Agonist and antagonist differ by a few letters and sit at opposite ends of what a compound does at a receptor. Misreading one for the other reverses the meaning of a mechanism label completely.
What it is not
An antagonist is not an inactive substance, and it is not the opposite molecule. It is doing something quite specific, namely occupying a site. An inverse agonist, a related and frequently confused term, goes further still by pushing a receptor below its normal resting level rather than merely blocking it.
Also called
- antagonist
- antagonists
- antagonism
- receptor antagonist
- blocker
- inverse agonist
Compounds carrying this term
None on file yet. This term is in the controlled vocabulary but no compound record currently uses it — which is a statement about our coverage, not about the term.