Ziconotide is a
nonopioid analgesic currently indicated as monotherapy, but frequently used in combination with
opioids, for the management of severe
chronic pain in patients for whom intrathecal (IT)
therapy is warranted and who are intolerant of, or whose
pain is, refractory to other treatments. There is a paucity of information regarding
ziconotide use in patients with
complex regional pain syndrome (CRPS). Seven cases in which IT
ziconotide was used in patients with CRPS were analyzed. All patients (4 male, 3 female; age range, 14 to 52 years) had experienced inadequate
pain relief with multiple conventional and interventional treatments. Three patients received
ziconotide monotherapy exclusively; 4 patients received
ziconotide monotherapy initially, then combination IT
therapy. The mean
ziconotide dose was 5.2 mcg/d (range, 0.5 to 13 mcg/
d) at initiation and 24.7 mcg/d (range, 0.06 to 146 mcg/
d) at the last available assessment. The mean duration of
ziconotide therapy was 3.1 years (range, 26 days to 8 years). At
ziconotide initiation, the mean visual analog scale (VAS) score was 89.3 mm (range, 75 to 100 mm); VAS scores decreased by a mean of 47.5% (range, 5% to 100%) at last assessment. Of the 5 patients who experienced substantial improvement in
pain,
edema,
skin abnormalities, and/or mobility with
ziconotide therapy, 2 have discontinued
ziconotide and are
pain free. Another patient experienced marked reversal of both
edema and advanced skin trophic changes. Adverse events included
urinary retention, depression, anxiety, and
hallucinations. Adverse events generally resolved spontaneously, with treatment, or with
ziconotide discontinuation/
dose reduction. Although further studies are required,
ziconotide holds promise as an effective treatment for CRPS.