**Pharmacovigilance of the Analgesic Therapy**

Silvia Ussai

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Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/67243

#### Abstract

Analgesics, the cornerstone for the alleviation of both acute and chronic pain, represent one of the most used classes of medications. While they are essential for the improvement of patients' quality of life, analgesic use is often associated with adverse drug reactions (ADRs) that might affect their usability in particular clinical situations. This indicates that a detailed knowledge of analgesic-derived ADRs is essential for the planning of an efficient pain relief strategy. This chapter reviews the ADRs associated with the two most commonly used analgesic classes, opioid and nonsteroidal antiinflammatory drugs (NSAID), discussing their common adverse effects and how these can influence their usability in clinical applications. With the publication in recent years of more and more long-term studies, this chapter also provides an overview of the potential risks of long-term analgesic use. This is particularly important for opioid analgesics, whose chronic use can lead to analgesic tolerance and addiction. A full description of potential problems deriving from analgesic use represents the first step in optimizing protocols for its safe application in clinical settings.

Keywords: Opioids, NSAID, ADRs, Analgesics, pharmacovigilance
