The following drugs exert their effects by binding to receptors and mimicking the effects of the endogenous ligand (i.e. are agonists):

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 3 retries using GPT-3.5.

Correct Answer: A

Rationale: Protamine sulfate is the antidote for Heparin. Heparin is an anticoagulant used to prevent blood clotting. Protamine sulfate works by binding to heparin, neutralizing its anticoagulant effects. Vitamin K is not the antidote for Heparin; it is used to reverse the effects of warfarin, another type of anticoagulant. Naloxone is an opioid antagonist used to reverse the effects of opioids, and Toradol is a nonsteroidal anti-inflammatory drug (NSAID) used for pain relief.

Correct Answer: C

Rationale: Propranolol undergoes extensive first-pass metabolism in the liver. When administered orally, propranolol is extensively metabolized by the liver before reaching systemic circulation, leading to reduced bioavailability. This process is known as first-pass hepatic metabolism, which significantly affects the drug's effectiveness and necessitates higher oral doses compared to other routes of administration.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 3 retries using GPT-3.5.