Ziconotide is:
Correct Answer: A
Rationale: Ziconotide, a non-opioid analgesic, blocks N-type calcium channels intrathecally. It's licensed in Europe and North America for chronic pain (e.g., cancer, neuropathic), delivered via pumps. Unlike opioids, it doesn't form granulomas at catheter tips those are opioid-specific complications. It's contraindicated in psychosis (e.g., schizophrenia) due to neuropsychiatric side effects (confusion, hallucinations), per prescribing guidelines. Hypogonadism isn't linked; that's an opioid effect via hypothalamic suppression. Tolerance occurs, requiring dose escalation, but it's manageable. Its licensure reflects extensive trials showing efficacy and safety for refractory pain, distinguishing it as a targeted, non-addictive option in intrathecal therapy, critical for patients intolerant to opioids.