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Intermediate Technical IVT

agonist

Pronunciation: AG-oh-nist

Medication that activates receptors to produce a biological response.

Full Definition

Medication that binds to and activates receptors to produce a biological response, mimicking the action of naturally occurring substances. In psychopharmacology, agonists can be full agonists (producing maximum receptor activation), partial agonists (producing submaximal activation even at full receptor occupancy), or inverse agonists (reducing receptor activity below baseline). Examples include dopamine agonists used in Parkinson's disease, GABA agonists for anxiety, and partial dopamine agonists like aripiprazole in antipsychotic therapy.

Usage

Usage note: Distinguish between full agonists, partial agonists, and inverse agonists when specificity is important.

In Context

  • "The serotonin receptor agonist effectively reduced migraine frequency." — Clinical study report
  • "Partial agonist properties allow for mood stabilization with reduced side effects." — Pharmacology review

Also known as

receptor activator

Contrasted with

antagonist blocker

Don't confuse with

partial agonist inverse agonist

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