Question

Which of the following statements about agonists is FALSE?

A. Partial agonist act at the same site as full agonist
B. Partial agonist can be as efficacious as full agonist if large amounts are used
C. Partial agonist may also have antagonistic properties
D. Partial agonist's efficacy is unrelated to their potency
E. None of the above

Answer 1

The false statement about agonists is that partial agonists can be as efficacious as full agonists by simply increasing the dosage. Partial agonists have a ceiling effect on efficacy, which is not overcome by larger amounts.

Step-by-step explanation:

The statement about agonists that is FALSE is: B. Partial agonist can be as efficacious as full agonist if large amounts are used. The efficacy of a partial agonist is not a matter of the quantity administered but rather an intrinsic property of the drug itself. While partial agonists do indeed act at the same site as full agonists (A) and have both agonistic and antagonistic properties (C), their efficacy is inherently lower than that of full agonists and cannot be matched by simply increasing the dosage. This is because partial agonists have a ceiling effect where increasing the dose does not increase the effect beyond a certain point. The efficacy of a partial agonist is also distinct from its potency, which is the amount of drug needed to produce a given effect (D).