Clonidine, an
alpha-2 adrenergic receptor agonist, has well-established role in acute perioperative
pain management. However, recently it has found increasing use in
chronic pain conditions as well. In this review, we systematically searched and analyzed the clinical studies from "PubMed," "PubMed central" and "Scopus" database for use of
clonidine in the
chronic pain. Quantitative meta-analysis was not possible as
clonidine has been used in various patient populations through different routes. However, qualitative analysis of nearly thirty clinical studies provides some evidence that
clonidine administered through epidural, intrathecal and local/topical route may be effective in
chronic pain conditions where neuropathy is a predominant component. It may also be effective where
opioids are of limited use due to inadequate
pain relief or adverse effects.