Chemical Stability of Admixtures Containing Ziconotide 25 mcg/mL and Morphine Sulfate 10 mg/mL or 20 mg/mL During Simulated Intrathecal Administration.

The chemical stability of an intrathecally administered analgesic combination may influence the frequency of pump refills necessary to maintain safe and effective analgesia. Previous work has shown that the stability of ziconotide at body temperature is reduced substantially by the presence of morphine sulfate 35 mg/mL. The current study was performed to evaluate the chemical stability of admixtures combining ziconotide with lower concentrations of morphine sulfate during simulated intrathecal infusion under laboratory conditions at 37 deg C.

Chemical stability of admixtures combining ziconotide with fentanyl or sufentanil during simulated intrathecal administration.

Although the U.S. Food and Drug Administration has not approved the combined use of intrathecal medications, practitioners frequently prescribe combination intrathecal therapy for patients who do not experience adequate analgesia with a single intrathecal agent; however, the chemical stability of an analgesic combination may influence the frequency of pump refills necessary to maintain safe and efective pain control.