gms | German Medical Science

Objective: Ziconotide (Prialt®) is a synthetic version of a peptide that is found in the venom of a marine snail, Conus magus. As an intrathecal non-opioid analgesic it is used for the intrathecal therapy of chronic pain, especially in cases of refractory pain or existing side effects of morphine.

Methods: We analysed clinical data of all patients, who were treated with intrathecal Ziconotide from April 2007 until September 2018 in our department.

Results: From 2007–2018, 13 patients were treated with intrathecal Ziconotide. Patients’ age was 44–71 years (median 58), with a male to female ratio of 6:7. The most common primary diagnosis (10/13 patients) was a failed back surgery syndrome (77%). Usually intrathecal Ziconotide was a 3rd line therapy (after morphine and hydromorphone). The average treatment time was 1233 days. Starting doses ranged from 1.2 to 2.4 µg/d (median 2.0). The maximum dose was 19 µg/d (median 6.4). Mean pain reduction was 2.5 on VAS. After discontinuation 75% returned to i.t. morphine. Only 4 patients are still treated with Prialt®. 85% of all patients (11/13) experienced adverse events. The most common side effects were psychiatric (memory impairment, dizziness, confusional state, visual defects, nausea) next to gait abnormality and urinary retention, that all were completely reversible after dose reduction.

Conclusion: Intrathecal Ziconotide can be an efficient alternative in the therapy of chronic refractory pain. Our therapy experience with Prialt® conforms to the current literature. Low doses at the start of Ziconotide application and a slow titration may allow patients to achieve an analgesic effect, while improving tolerability and decrease the risks of side effects. Furthermore intrathecal Ziconotide can be used as a drug holiday alternative for morphine. Nevertheless, a trusting doctor-patient relationship is important, as well as a careful history of preexisting psychotic disorders.