[1] For example, sunburn can cause temporary allodynia, so that usually painless stimuli, such as wearing clothing or running cold or warm water over it, can be very painful.

Allodynia may also be caused by some populations of stem cells used to treat nerve damage including spinal cord injury.

[5] Mechanoreceptors can influence the output of nociceptors by making connections with the same interneurons, the activation of which can reduce or eliminate the sensation of pain.

[9] All of these changes ultimately affect the circuitry inside the spinal cord, and the altered balance of signals probably leads to the intense sensation of pain associated with allodynia.

[11] There is a substantial body of evidence that the so-called sensitization of the central nervous system contributes to the emergence of allodynia.

[14] The mechanism responsible for sensitization of the central nervous system at the spinal cord level differs from that in the thalamus.

Tumor necrosis factor-alpha (TNF-alpha) and its receptor are the molecules that seem to be responsible for the sensitization of neurons in the dorsal horns of the spinal cord.

Macrophages and lymphocytes infiltrate the spinal cord, for example, because of injury, and release TNF-alpha and other pro-inflammatory molecules.

For example, many non-steroidal anti-inflammatory drugs, such as naproxen, can inhibit COX-1 and/or COX-2, thus preventing the sensitization of the central nervous system.