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.
Keywords: Chronic pain; clonidine; neuropathy.