Which of the following drugs would be useful to treat the patient's condition of repeated head jerking, blinking, and grimacing?

Correct Answer: B

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

Correct Answer: D

Rationale: The opening of K+ channels on postsynaptic neurons is a key molecular action that mediates the analgesic effect of opioids like morphine. This action leads to hyperpolarization of the neuron, reducing its excitability and inhibiting pain transmission. Therefore, in a patient with severe pain due to multiple fractures, the opening of K+ channels by morphine would be the most likely mechanism responsible for the analgesic effect.

Correct Answer: D

Rationale: The patient self-injected what he believed to be heroin, which is commonly sold on the street. Fentanyl is a potent synthetic opioid that is often mixed with or sold as heroin due to its powerful effects. Therefore, the patient most likely took Fentanyl, as it is frequently associated with street drugs like heroin.

Correct Answer: A

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

Correct Answer: D

Rationale: Meperidine is a commonly used opioid analgesic that is often used in detoxification programs due to its ability to help manage withdrawal symptoms. In this case, the patient was undergoing a detoxification program supervised by surgery, and a drug was administered intravenously. Meperidine is a likely choice as it can help alleviate withdrawal symptoms and manage pain during the detoxification process.