Adrug that blocks the effects of a neurotransmitter is a(n) ; a drug that mimics or increases the effects is a(n)

A drug that blocks the effects of a neurotransmitter is known as antagonists. A drug that mimics or increase the effects is known as agonists.

Explanation:

An agonist is a chemical that binds to a receptor and activates the receptor to produce a biological response. Whereas an agonist causes an action, an antagonist blocks the action of the agonist. A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. They are sometimes called blockers; examples include alpha blockers, beta blockers, and calcium channel blockers..

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