Introduction
Leaving aside the problems of pain assessment, empirical treatment of presumed painful conditions will continue, and it is not unreasonable to assume that analgesic therapies shown to be effective in people are also likely to be effective in animals. A growing body of data from well-controlled trials of analgesic efficacy in animals is now also becoming available, but even when these have not been completed, results of nociceptive tests can be used to guide dosing regimens. Analgesics can be broadly divided into two groups, the opioids or narcotic analgesics and the NSAIDs such as aspirin. Local anaesthetics can also be used to provide post-operative pain relief by blocking all sensation from the affected area.