Answer:
1.Agonists
2.Antagonists
Step-by-step explanation:
An agonist drug attaches to both the receptor which induces the reaction inside the cell. An antagonist can attach to the very same receptor, but will not generate a response, rather it stops the receptor from a natural agonist.
Antagonism can be successful and offset by elevated agonist levels. Unmanageable antagonists are firmly bound to a transmitter and therefore are not removed by an external agonist.