What is the mechanism of action (MOA) of ziconotide?

The mechanism of action of ziconotide is primarily focused on its ability to inhibit calcium channels. Ziconotide is a non-opioid analgesic that is administered intrathecally (directly into the spinal fluid), and it works by binding to N-type voltage-gated calcium channels in the nervous system. This binding effectively blocks the influx of calcium ions into neurons, which subsequently reduces the release of several neurotransmitters involved in pain signaling. By interrupting this process, ziconotide can help alleviate pain, particularly in patients who have not responded well to other forms of treatment, such as opioids.

This mechanism is especially significant in the context of chronic pain management as it offers an alternative to opioids, which can be associated with various side effects and risks of addiction. Other options presented, such as inhibiting opioid receptors, increasing serotonin levels, or blocking sodium channels, do not accurately describe the action of ziconotide. The focus on calcium channel inhibition highlights the specific pharmacological pathway through which ziconotide exercises its analgesic effects.