Pain is an unpleasant sensory and emotional experience associated with actual or potential damage, or described in terms of such damage. Animals must not be subjected to unnecessary pain.

Successful alleviation, minimization or prevention of pain in laboratory animals is critically dependent upon:

• accurate pain assessment
• use of anesthesia
• use of analgesia
• use of humane endpoints
• knowledge of humane killing methods

When planning an experiment, investigators should consult with their institution's clinical veterinarian about using pain control measures in their research protocols.

Ways to implement pain-controlling refinements into animal use protocols include:

• adapting existing methods of pain assessment for the species
• if pre-existing pain assessment methods are unavailable, consider devoting resources to developing a scoring system
• if pain scoring is not possible, determine the analgesic protocol in consultation with a veterinarian
• use analgesic dose rates that have been established in studies that used pain scoring systems
• when data on pain scoring is not available, estimate doses from results of analgesiometric studies using tonic (longer lasting) nociceptive stimuli (e.g., late phase formalin test)
• use pre-emptive analgesia and multimodal strategies
• attempt to evaluate the efficacy of the analgesic regimen selected
• regularly review pain management procedures to ensure they represent current best practice

This section was adapted from the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) website.