Do the potential benefits outweigh the risks? An update on the use of ziconotide in clinical practice

Abstract

Ziconotide is a selective and potent blocker of N-type voltage-gated calcium channels. It was approved by the Food and Drug Administration in 2004 and by the European Medicines Agency in 2005 for the treatment of severe chronic pain in patients needing intrathecal analgesia (ITA). The aim of this paper is to provide a practitioner-oriented, educational, narrative, up-to-date review on the use of ziconotide in clinical pain medicine. Of special concern regarding safety is the partial incongruity between dosing statements in the Summary of Product Characteristics and novel low-dosage, slow uptitration recommendations. Even though ziconotide has obvious advantages compared to opioids, pain practitioners pondering the use of ziconotide nonetheless have to balance its proved potential analgesic effect against its neurological side effects, with special consideration being given to dosing and neuropsychiatric dangers. Using a seesaw analogy, the paper discusses what factors pain physicians should weigh in when considering ziconotide as ITA drug, the non-opioid advantages of ziconotide being counterbalanced by its potential psychiatric side effects. Ziconotide is an important part of the armamentarium of modern interventional pain medicine. If ITA is deemed necessary, ziconotide is a rational alternative, at least in chronic (neuropathic) non-cancer pain. However, in many European countries, ziconotide treatment is only available in a few (if any) centres. The safety profile of ziconotide is not fundamentally more worrying than that of opioids or cannabinoids; it is just different. This paper provides a concise, up-to-date and clinically-oriented summary of the use of ziconotide in clinical practice, not least concerning safety and dosage issues.