chapter  37
Controlled Release Pain Management Systems
Pages 20

Pain, a nearly universal experience, is defined as “an unpleasant sensory and emotional experi­ ence associated with actual or potential tissue damage, or described in terms of such damage” by the International Association for the Study of Pain (Suri et al., 1997). The types and mech­ anisms of pain are given in Table 1. In addition to these, pain perception involves psychologi­ cal components that may not be defined completely in physiological terms.