Acute Cardiovascular Toxicity of Low-Dose Intrathecal Ziconotide

Abstract

Dear Editor, Ziconotide, marketed in the United States as Prialt® (Jazz Pharmaceuticals, Dublin, Ireland), is the first in a new class of non-opioid pain medication targeting N-type voltage-gated calcium channels (VGCCs) approved after a series of landmark clinical trials in the 1990s ⇓. Due to its limited bioavailability in the central nervous system (CNS), it is primarily administered via chronically implanted intrathecal (i.t.) pump. Ziconotide has a number of dose-limiting side effects, typically neurological or psychiatric symptoms. Here, we report a case where a remarkably short, low-dose exposure to i.t. ziconotide produced severe cardiovascular and neurological impairment reversing over the course of 24 hours. Patient SK, a 42-year-old man, had a 3.5-year history of lower extremity complex regional pain syndrome type I when he presented for an i.t. ziconotide trial, having failed standard opioid analgesics, antineuropathics, epidural injections, lumbar sympathetic blocks, and a spinal cord stimulator trial. His medical history was significant for severe obesity (body mass index = 39.5), hypertension, major depressive disorder, and obstructive sleep apnea. He had sustained moderate trauma to his left foot from a falling object in a store, followed by progressive allodynia, hyperesthesia, and hyperalgesia, originating in the left foot and ultimately affecting his entire left side including …