Treatment challenges and complications with ziconotide monotherapy in established pump patients

The U.S. Food and Drug Administration (FDA) recently approved Ziconotide intrathecal infusion for the management of severe chronic pain in patients for whom intrathecal therapy is warranted, and who are intolerant of, or refractory to, other methods of treatment, including intrathecal morphine. Ziconotide is approved as a monotherapy, but there are challenges associated with the decision to wean intrathecal opioids for Ziconotide alone. Maintaining adequate analgesia and managing opioid withdrawal symptoms may be difficult. Additionally, a variety of adverse physiological, cognitive and psychiatric events may be associated with this new drug. Patients with pretreatment psychiatric disorders may be at increased risk for treatment complications.

To present a report of a case series describing treatment challenges and complications associated with the decision to convert established pump patients from intrathecal opioid therapy to Ziconotide monotherapy.

Three established pump patients, refractory to intrathecal opioid therapy, were converted to Ziconotide monotherapy. All of these patients experienced significant emotional distress or psychological symptoms that threatened the success of the treatment. Achieving adequate analgesia, reducing Ziconotide to mitigate adverse physiological effects, managing opioid withdrawal symptoms, and supportive psychological consultation were combined to achieve successful outcomes in two of our three patients.

This report describes challenges associated with the decision to convert established pump patients from intrathecal opioid therapy to Ziconotide monotherapy. Inadequate analgesia, adverse medication effects, and opioid withdrawal symptoms can precipitate a stressful situation that may be perceived as dangerous or threatening by patients who are predisposed to anxiety. Screening patients for psychiatric disorders, anxiety-proneness and/or vulnerability to stress should be considered to reduce the risk of treatment complications. A multimodal approach is strongly advocated, including rapid responses of treating physicians and nurses along with strong psychological support.