**Pharmacotherapy of Chronic Pain**

Marta Vázquez and Pietro Fagiolino

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/66444

#### **Abstract**

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32 Pain Relief - From Analgesics to Alternative Therapies

Comparative Medicine. December, 2006;**56**(6):487‐492

In the past two decades, many preclinical works have been carried out assisting in our understanding of the underlying pathophysiological mechanisms that cause chronic pain. Chronic pain involves multiple pathophysiological mechanisms with peripheral and central components. This research in basic and clinical research has greatly expanded the options for analgesic pharmacotherapy. This chapter gives information regarding the major classes of medication used to assist in the management of chronic pain, includ‐ ing nonopioids analgesics such as NSAIDs and acetaminophen, opioids analgesics, antidepressants and anticonvulsants and an emerging area as the field of cannabinoids is. Importantly, chronic pain treatment encompasses multiple agents to take advantage of synergistic mechanism of actions, but drug‐drug interactions have to be taken into account in order to avoid lack of efficacy or toxicity.

**Keywords:** nonopioid and opioids analgesics, antidepressants, anticonvulsants, cannabis, interactions, chronic pain
