Moxonidine, a mixed alpha(2)-adrenergic and imidazoline receptor agonist, identifies a novel adrenergic target for spinal analgesia.

Moxonidine is a mixed alpha(2)-adrenergic and imidazoline receptor agonist with an improved side effect profile compared to clonidine. Intrathecal (i.t.) moxonidine has been found to possess analgesic activity that, in contrast to the majority of alpha(2)-adrenoceptor (alpha(2)AR) agonists, does not require activation of the alpha(2A)AR subtype, which mediates many of the side effects associated with alpha(2)AR use. In addition, moxonidine (i.t.) interacts in a synergistic manner with opioid agonists and this synergy is retained in neuropathic pain states. Moxonidine may therefore be clinically useful in the treatment of chronic neuropathic pain, either alone or as a coadjuvant with opioids.