Nociceptive Pain and Inflammation
Inflammation and nociceptive pain go hand-in-hand.
Inflammation is initiated upon tissue injury and sets off a cascade of biochemical reactions that prime the nervous system for pain sensing. Moreover, long-term inflammation reinforces adaptive changes in the nervous system that can cause the sensation of pain to become exaggerated or inappropriate (Ji 2011). For example, inflamed tissue (e.g., an arthritic knee) may be excessively tender and even a light touch might cause pain, a phenomenon known as allodynia.
Nociceptive pain does not occur spontaneously, it must be triggered within the nervous system. This task is accomplished by specialized receptors called nociceptors.
When you experience an injury, several inflammatory mediators including prostaglandins, tumor necrosis factor-alpha (TNF-α), interleukin 1β (IL-1β), and interleukin-6 (IL-6) are released at the site of the injury and interact with nociceptors, facilitating the transmission of pain signals through the nervous system. If you have a chronic inflammatory condition (e.g., osteoarthritis), then increased levels of inflammatory mediators at the affected site (e.g., a joint), as well as systemically, predispose you to increased pain sensations.
Therefore, taking steps to ease inflammation is an effective means of interfering with the process of pain sensitization. This is why drugs like acetaminophen (the active ingredient in Tylenol®) and ibuprofen, which are anti-inflammatory in nature, relieve pain. Unfortunately, though these drugs and others like them are very effective for reducing inflammation and pain, they often cause alarming side effects, which compromises their long-term risk vs. benefit profile (see The Potentially Lethal Side Effects of Over-the-Counter Pain Medications; below).
A variety of natural anti-inflammatory compounds are able to target inflammation by reducing the synthesis of inflammatory mediators, or modulating inflammatory pathways. As will be discussed later, many natural compounds exert powerful anti-inflammatory activity without causing unwanted side effects. See Targeted Nutritional Interventions.