Topical treatments for pain.

Topical analgesics exert their analgesic benefit locally and without significant systemic absorption. The mechanism of the topical analgesic is unique to the specific medication. Key differences between topical and transdermal analgesics are discussed in this article. A new term, targeted peripheral analgesics, has been suggested to replace the term topical analgesics, but is not in widespread use. Topical analgesics have been studied in an increasing number of painful clinical conditions; the results of many of these studies are summarized in this review. Recent data suggest that at least one topical analgesic, although applied peripherally, may result in central nervous system alterations of pain processing.